
A cowering Nikolas Cruz was comforted by his public defender as he was ordered held without bail during his first court appearance on Thursday, in connection to the deadly shooting at a Parkland, Florida high school on Wednesday that left 17 dead and 14 injured.

The 19-year-old wore an orange jump suit and shackles on his wrists and ankles as he was officially charged with 17 counts of premeditated murder.

He kept his eyes down and didn't speak in court today, other than to confirm his name with a polite 'yes ma'am' to the judge.

Standing next to him was his public defender, Melisa McNeil, who comforted him by putting a hand around his shoulder.

After the hearing, Cruz's defense team revealed that he was on suicide watch and that he understood the magnitude of his actions.

McNeill told reporters gathered outside the courtroom that her client was sad and remorseful.

'He's sad. He's mournful. He's remorseful. He is fully aware of what is going on, and he's just a broken human being,' she said.

She became emotional while speaking to reporters, saying she's fully aware of the impact the shooting has had on the community, as a parent herself.

'I had to have the exact same conversation that every parent in Broward had to have with their children this morning, then I had to walk and meet with him,' McNeill said. 'I'm fully aware of the impact this has on the people who live here.

According to her LinkedIn, she has worked in the homicide division of the Broward public defender's office since 2000.

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A cowering Nikolas Cruz (center, in orange) was ordered held without bond during his first court appearance on Thursday, where he was officially charges with 17 counts of premeditated murder.

Cruz (left and right in orange) mostly kept his head down for the brief bond hearing on Thursday

'He's sad. He's mournful. He's remorseful. He is fully aware of what is going on, and he's just a broken human being,' Cruz's public defender Melissa McNeil (pictured) said after the court hearing

Gordon Weekes (pictured), who is also representing Cruz, said the teen 'is deeply troubled and he has endured significant trauma that stems from the loss of his mother'

Another member of the defense team, Gordon Weeks, was brought to tears as he addressed reporters, telling them that Cruz 'recognizes' what he has done and is 'deeply sad'.

'He is dealing with the shock of all this that's going on,' Weeks said.

McNeill and Weeks said that Cruz suffers from autism, depression and has dealt with significant psychological problems - all without the sort of support system that most people have.

'When your brain is not fully developed, you don't know how to deal with these things,' McNeil said. 'That's the child I'm sitting across from.'

Weeks added: 'The child is deeply troubled and he has endured significant trauma that stems from the loss of his mother.'

Florida Attorney General Pam Bondi has said she is 'certain' prosecutors will be seeking the death penalty for the teen shooter.

Florida gunman Nikolas Cruz's arrest affidavit The complaint affidavit against Nikolas Jacob Cruz reveals he has been charged with 17 counts of pre-meditated murder and confirms both of his parents are dead. The documents say that at 2.23pm on February 14, multiple 911 calls were received of a shooting taking place at the Marjory Stoneman Douglas High School. Cruz's height is give as 5'87, his weight as 128 lbs and birthplace United States of America. The affidavit outlines the chain of events that happened during the Marjory Stoneham Douglas High School massacre According to the document, Cruz was first spotted by an unnamed witness after arriving by Uber Both of Cruz's parents are deceased and he is living with a family, who give him his own room The affidavit states that Cruz admitted being the shooter and that he planned to blend in with crowd after carrying out the killings Cruz was charged with a total of 17 counts of premeditated murder relating to the shootings Cruz made his first court appearance accompanied by a public defender 'Multiple deceased persons were observed at the scene,' read the affidavit, which continues that 'the shooter attempted to blend in with fleeing students and was able to elude arriving officers'. A sworn statement from a witness, whose name was redacted, said he recognized Cruz as a 'troubled former student' who arrived in a 'small goldish colored vehicle' The witness stated Cruz was wearing a maroon shirt, black pants and a black hat and was carrying a black duffel bag and black backpack. He was walking 'purposefully' towards school buildings the witness said. 'Within a minute he heard gunshots and called a "Code Red" indicating an emergency on campus,' the affidavit reads. According to the affidavit, both Cruz's parents are deceased and he was staying with a family who have given him his own room in their house. 'Cruz stated that he was the gunman and entered the school campus armed with an AR-15 and began shooting students that he saw on the hallways and on the school grounds'. 'Cruz admitted that as students began to flee on foot he decided to plan to discard the AR-15 and vest with additional magazines so he could blend in with the crowd.' Advertisement

Broward County Sheriff Scott Israel revealed on Thursday afternoon that Cruz had tried to mix in with a group of students fleeing the school before stopping at fast food restaurants after the attack.

The sheriff said Cruz headed to a Wal-Mart and bought a drink at a Subway restaurant before walking to a McDonald's. Cruz was confronted by a police officer and taken into custody about 40 minutes after leaving the McDonald's.

Cruz was initially taken to the hospital to be treated for 'labored breathing'.

He was soon released to the police who spent most of the night questioning Cruz, trying to make sense of the horrific school shooting - now the third deadliest in American history.

The fact that it was the 30th mass shooting so far this year has spurred activists to call on Congress again to revamp the nation's gun control policies. President Trump, a staunch defender of the National Rifle Association, said at a press conference on Thursday that the real issue lawmakers need to tackle is mental health, not guns.

Meanwhile, details are starting to emerge about the shooter, who recently was orphaned, stopped getting mental health treatment about a year ago and even had ties to a white supremacist group.

Students at Marjory Stoneman Douglas High School painted the picture of a weird and disturbed teen who sold knives out of a lunchbox, bragged about killing animals and was finally kicked out of school for fighting and carrying bullets in his backpack.

An FBI official also said Thursday that they were warned - not once, but twice - about the shooter. One of the warnings came in September, from a bail bondsman in Mississippi who alerted the feds about an alarming online message Cruz wrote saying he was 'going to be a professional school shooter'

This photo provided by the Broward County Jail shows Nikolas Cruz, the teen suspected of killing 17 and injuring more than a dozen in a school shooting on Wednesday in Florida

Cruz was dressed in a hospital uniform as he was seen leaving the Broward County Sheriff's Office early Thursday morning

He was given an orange jumpsuit after arriving at the county jail Thursday morning

Ben Bennight says he alerted the FBI to a comment shared by Cruz on one of his YouTube videos back in September. He says the FBI was quick to respond to the concerning statement, arriving at his office the very next day to find out if he knew anything about the young man.

He didn't hear from the FBI again until after the shooting on Wednesday. At a press conference Thursday morning, an FBI official said they followed up on the report but were 'unable to further identify the person who made the comment'.

Broward County Mayor Beam Furr also revealed that Cruz had been getting treatment at a mental health clinic for a while, but hadn't been back to the clinic in more than a year.

'It wasn't like there wasn't concern for him,' Furr told CNN. 'We try to keep our eyes out on those kids who aren't connected. … In this case we didn't find a way to connect with this kid.'

President Trump and former President Obama weighed in on the tragedy with tweets on Thursday

Trump spoke about the shooting at a mid-morning press conference from the White House

Authorities offered no immediate details about Cruz or his possible motive, except to say that he had been kicked out of the high school, Marjory Stoneman Douglas High School, which has about 3,000 students.

Officials wouldn't say why exactly Cruz had been expelled, but fellow students said it was because he got into a fight with his ex-girlfriend's new boyfriend and because he was caught with bullets in his backpack.

Authorities quickly started dissecting the shooter's social media accounts in a bid to piece together the motive. Sheriff Israel reported that some of things the shooter had been posting was 'very disturbing'.

In one Instagram post, Cruz posted a screengrab of Google search results for 'what does allahu akbar' mean. Allahu Akbar means 'God is great' in Arabic, and is something Islamist terrorist often shout before attacks.

He captioned the photo: 'Well at least we know what it means when a sand durka [a racial expletive for an Arab person] says 'allahu akbar' [laughing face emojis].'

ABC News reported Thursday that Cruz appeared to have ties to a white nationalist group called the Republic of Florida. A spokesman for the group confirmed Cruz was a member.

Cruz's Instagram is filled with disturbing posts of what appears to be himself showing off weapons, his face sometimes covered, along with other disturbing images and captions

In one Instragram post, Cruz posted a screengrab of Google search results for 'what does allahu akbar' mean. Allahu Akbar means 'God is great' in Arabic, and is something Islamist terrorist often shout before attacks. He captioned the photo: 'Well at least we know what it means when a [racial lslur] says 'allahu akbar' [laughing face emojis].'

Cause for concern: 'I'm going to be a professional school shooter.' wrote Cruz on a video that had been shared by YouTube vlogger Ben Bennight (Cruz's comment above)

The group describes itself as a 'white civil rights organization fighting for white identitarian politics' and seeks to create a 'white ethnostate' in Florida.

The leader of the group, Jordan Jereb, told the Anti-Defamation League that Cruz was brought into the group by another member and had participated in training exercises with the group.

Jereb said that Cruz was not ordered to pull off the shooting and that they are not a terrorist organization.

He added to ABC News that he had not seen Cruz in 'some time' but after the shooting on Wednesday 'he knew he would be getting this call'.

He also said he had 'trouble with a girl' and he believed the timing of the attack, carried out on Valentine's Day, wasn't a coincidence.

A law enforcement official says he knows of 'no known ties' between the suspect who confessed to a deadly mass shooting at a Florida high school and a white supremacist group.

Lt. Grady Jordan is a spokesman for the Leon County Sheriff's Office in Tallahassee, where the white nationalist militia known as the Republic of Florida is based.

He says his office has 'very solid' information on the group and 'there's no known ties that we have that we can connect' 19-year-old Nikolas Cruz with the group.

Cruz suffered a major blow in November when his adoptive mother Lynda Cruz, 68, died of pneumonia. Lynda was apparently the only person Cruz was close with.

'Lynda was very close to them,' her sister-in-law Barbara Kumbatovic told The Washington Post. 'She put a lot of time and effort into those boys, trying to give them a good life and upbringing.'

Lynda and her husband, who died of a heart attack several years ago, adopted Cruz and his biological brother, Zachary, after the couple moved from Long Island in New York to Broward County. Cruz was an infant when he was adopted. It's unclear if he was adopted from the U.S. or aboard. Adopted children from abroad sometimes have issues adjusting due to neglect in their orphanages, especially children from Russia.

Tyra Hemans, a 19-year-old senior at Marjory Stoneman Douglas High School, sobs as she holds signs honoring slain teachers and friends near the police cordon around the school in Parkland Florida, U.S., February 15, 2018

A man with a sign is seen after the news conference in the hallway outside the courtroom where Nikolas Cruz appeared via video at a bond court hearing after being charged with 17 counts of premeditated murder, in Fort Lauderdale, Florida, U.S., February 15, 2018

The White House flag was lowered to half-staff on Thursday in remembrance of the victims who died in the shooting on Wednesday

The shooting was the 30th mass shooting of the year, a fact that has propelled many, including Kim Kardashian, to demand Congress enact stricter gun control laws

A group of police officers stand guard in front of the entrance of the Marjory Stoneman Douglas High School, on Thursday

Florida Gov. Rick Scott, right, speaks to reporters at a Thursday morning press conference about the shooter

City, county and state officials release balloons in honor of the victims during a prayer vigil for the Marjory Stoneman Douglas High School shooting at Parkridge Church in Coral Springs, Florida on February 15, 2018

While his brother was quiet and liked to stay indoors, Cruz constantly got into trouble and appeared to have 'emotional issues'.

'Lynda dealt with it like most parents did. She was probably too good to him,' Kumbatovic said. 'She was a lovely woman. She was a hard-working woman. She made a beautiful home for them. She put a lot of effort and time into their schooling, their recreation, whatever they needed. She was a good parent. And she went over and above because she needed to compensate for being a single parent.'

She added: 'I don't think it had anything to do with his upbringing. It could have been the loss of his mom. I don't know.'

Longtime Cruz family neighbors Malcolm and Christine Roxburgh told the Sun Sentinel that the police came to the boy's house many times, as he used to get in trouble and harass people. He didn't have an arrest record though.

Malcolm Roxburgh said a neighbor across the street kept pigs, and Nicolas Cruz targeted the family.

'He didn't like the pigs and didn't like the neighbors, so he sent over his dog over there to try to attack them,' Roxburgh said. Another neighbor, Shelby Speno, said she once witnessed Cruz shooting at chickens owned by another resident.

Roxburgh's wife said she once caught Cruz peeking in her window.

'I said, 'What are you doing here?' He said he was looking for golf balls. I said, 'This isn't the golf course,'' she said.

And, the couple said, when the boy didn't want to go to school, he would bang his head against a cement wall. They were scared of him. 'He could have killed any of us,' Christine Roxburgh said.

After their mother's death, the boys were left in the care of a family friend - but Cruz didn't stay there very long.

Classes for the rest of the week have been cancelled at the school in Parkland, Florida (pictured above on Thursday)

There continued to be a police presence on the campus on Thursday. Investigators were no doubt continuing to comb the scene for clues

Pictured above is the Broward County Jail where Cruz is being held pending his trial

Unhappy there, Cruz asked to move in with a friend at a mobile home park in northwest Broward. The friend's family agreed and Cruz moved into his own room in the home around Thanksgiving.

'The family brought him into their home,' the family's attorney, Jim Lewis, said. 'They got him a job at a local dollar store. They didn't see anything that would suggest any violence. He was depressed, maybe a little quirky. But they never saw anything violent. … He was just a little depressed and seemed to be working through it.'

Cruz brought his AR-15 rifle with him to the family's home, where it was kept in a locked cabinet that the teen had a key to. Sources told CNN that the gunman purchased the rifle in the past year and passed a required background check to obtain it. Two federal law enforcement officials said the Smith & Wesson M&P rifle was purchased legally at Sunrise Tactical Supply in Coral Springs, Florida. Federal law allows people 18 and over to legally purchase long guns. At 21, people can legally buy handguns from a licensed dealer.

While living with the family, Lewis started going to a school for at-risk youth. Usually every morning, the father of the family would drive Cruz to school, but on Wednesday he overslept and then gave a cryptic reason why.

'He said, 'It's Valentine's Day and I don't go to school on Valentine's Day,'' Lewis said.

Lewis said the family is devastated and didn't see this coming. The family's son was a junior at the school and was there when the shooting happened. Lewis said the family is cooperating and no one there is suspected of wrongdoing, he added.

The family's cream-colored home was empty Thursday morning but in the backyard a bullet-riddled Bud Light can was stuck on a twig of an avocado tree overlooking a creek.

How were at least 16 warning signs missed for Nikolas Cruz? 1. 'I'm going to be a professional school shooter' Nikolas Cruz left a comment on a YouTube video back in September using his own name that simply read: 'I'm going to be a professional school shooter' 2. FBI was warned about the comment but couldn't identify him Vlogger Ben Bennight alerted the FBI to the comment shared by Cruz. The FBI was quick to respond, arriving at his office the next day but only after Bennight called a local field agent, revealing his initial attempts to send in a screengrab of the comment failed when the email address he found listed on the agency's website came back with a domain error saying it did not exist. The FBI was unable to identify the person who posted the comment. 3. Bought an AR-15 age 18 After Cruz's mother died, he eventually moved in the the family of a former classmate, where he brought his AR-15 which was kept in a locked cabinet that he had the key to. He was able to purchase the rifle in the past year and passed a required background check. Federal law allowed people 18 and over to legally purchase long guns. At 21, people can legally buy handguns from a license dealer. Cruz was also studying marksmanship in the Army Junior Reserve Officers' Training Corps. 4. Troubling Instagram page Cruz's Instagram page is filled with disturbing posts of what appears to be himself showing off with weapons with his face covered, asking for advice on buying firearms, and making racist comments about Muslims. 5. Was a member of a white nationalist group and came to training exercises Jordan Jereb claims that Cruz was a member of the Republic of Florida, which aims to make Florida its own white-entho state. Jereb claimed Cruz, who was adopted, was brought up in the organization by another member and he reportedly carpooled to at least two training exercises held by the group. 6. Boasted about hurting animals Students who say they knew Cruz claimed he liked to kill animals. 'He was crazy because he liked to kill small things, like little animals - frogs and other animals like that and he just had a crazy mind,' one told 10ABC news. Another classmate claims he would tell him he shot rats with a BB gun. 7. Took knives and bullets to school Former classmate Joshua Charo, 16, said all he 'would talk about is guns, knives and hunting'. Another student said he started selling knives out of a lunchbox when he started high school, while he was also found to be carrying bullet casings in his bag. 8. Was banned from carrying a backpack Jim Gard, a math teacher, who had Cruz in his class last year, said he believes the school sent out an email warning teachers he shouldn't be allowed on campus with a backpack. 'There were problems with him last year threatening students and I guess he was asked to leave campus'. 9. Expelled for fighting The deeply troubled 'loner' was expelled last year for 'fighting over his ex-girlfriend' with her new boyfriend. 10. Abusive to his ex-girlfriend Students claim the gunman was abusive to his girlfriend 11. Stalked another girl Mr Gard also claimed that he was taken with another student 'to the point of stalking her', while another student who claims to have been friends with Cruz said he had to cut him off because he started 'going after' and 'threatening' a female friend of his. 12. Peeping Tom Neighbor Christine Rosburgh said she, and all the other neighbors, were terrified of the teen who would bang his head against a cement wall if his legal guardians tried to send him to school. She also claims she caught him peeking in her window and when she confronted him, he said he was looking for golf balls. 'I said, "This isn't the golf course". 13. Stopped his mental health treatment Cruz had been getting treatment at a mental health clinic, but stopped about a year ago and dropped off the radar. He was showing signs of depression. Broward County Mayor Beam Furr said: 'It wasn't like there wasn't concern for him. We try to keep out eyes out on those kids who aren't connected... In this case, we didn't find a way to connect with this kid.' 14. Possible fetal alcohol syndrome Natalie Brassard, a program director at the non-profit FASCETS, which works with FASD children, said some of Cruz's characteristics 'suggest that he might have been living with an invisible brain-based condition - it could have been FASD or many others.' Conditions of FASD can range from mild to severe but can include learning disabilities, intellectual disability or low IQ, poor reasoning and judgment and a host of other issues. 15. Orphaned Cruz's adoptive mother, Lynda Cruz, 68, died of pneumonia in November last year. She was one of the only people that was remotely close to Cruz. His adoptive father Roger Cruz died of a heart attack several years ago. After his mother died, he and his brother were left in the care of family friend Barbara Kumbatovich, of Long Island, New York. He is believed to have lived for a few weeks at the Lantana Cascade mobile-home neighborhood with a different family friend before moving in with a former classmate's family in Parkland around Thanksgiving. 16. Disturbing posts on Snapchat Cruz was investigated by state authorities in 2016 after he filmed himself cutting his own arms on Snapchat and saying he wanted to buy a gun. He posted the video on the social media app in September 2016, 17 months before he allegedly committed the school shooting. He posted the Snapchat clip just days after turning 18 year of age and shortly after he broke up with his girlfriend ‘who was cheating on him,’ his mother told investigators. Advertisement

Pictured above is the mobile home where Cruz had been staying with a friend's family before the shooting

In the backyard of the home, beer cans and plates were set up as shooting targets

The backyard of the home on Easter Cay Way is littered with garden furniture and toys. Eerily, a Hot Wheels toy in a container is still beeping. A tan Kia Soul stands in the driveway

Above, a look at a storage shed on the property. No one appeared to be home on Thursday

A paper plate, apparently a shooting target, was on another tree.

Few people on the Lantana Cascades estate speak English. One neighbor who would not give his name said he only met Cruz once when the people in the house introduced him.

'He seemed like a nice kid but it was only the once,' the elderly man said. 'Then he was gone. I never saw him again.'

The backyard of the home on Easter Cay Way is littered with garden furniture and toys. Eerily, a Hot Wheels toy in a container is still beeping. A tan Kia Soul stands in the driveway.

Another neighbor, whose house on a neighboring street overlooks the home where Cruz had been staying, described Wednesday night on Lantana Cascades as 'a madhouse.'

'Dozens of police came. It was shortly after 5pm.

'They taped two whole streets off and made those nearest the house get out. I stayed though.

'I saw them go in and bring a lot of stuff out, but it was dark so I couldn't see what.'

Nikolas Cruz, 19, was arrested after he stormed Marjory Stoneman Douglas High School in Parkland on Wednesday afternoon armed with an assault rifle

The suspect, wearing a maroon colored top, is taken into custody two hours after opening fire on his high school

Authorities inspect the AR-15 rifle the teen gunman used in the mass shooting on Wednesday

The suspected gunman was checked out at a hospital after his arrest (above in a hospital gown) and is now being held at a secure location in a public building

Students called Cruz 'weird' and a 'loner' - even those who'd been friendly with him said they hadn't seen him in more than a year since his expulsion.

Dakota Mutchler, 17, recalled Cruz posting on Instagram about killing animals and said he had talked about doing target practice in his backyard with a pellet gun.

I think everyone had in their minds if anybody was going to do it, it was going to be him. Dakota Mutchler, Stoneman Douglas High student

'He started going after one of my friends, threatening her, and I cut him off from there,' Mutchler said.

He said students weren't surprised officials had identified Cruz as the shooter: 'I think everyone had in their minds if anybody was going to do it, it was going to be him.'

Victoria Olvera, a 17-year-old junior at the school, said Cruz was expelled last school year because he got into a fight with his ex-girlfriend's new boyfriend. She said he had been abusive to his girlfriend. Another student said that part of the reason Cruz was expelled was that he was caught carrying bullets in his backpack.

Matthew Walker, a 17-year-old student at the school, told WFOR-TV that all his classmates 'knew it was going to be him.'

Broward Sheriff Scott Israel said Cruz was a former student at the school but had been expelled for unknown 'disciplinary reasons' last year

'A lot of people were saying it was going to be him,' he said. 'A lot of kids threw jokes around saying that he was going to be the one to shoot up the school. It turns out that everyone predicted it. That's crazy.'

'He was going class to class just shooting at random kids,' he said. 'Everything he posts (on social media) is about weapons. It's sick.'

One teacher said he had been identified as a potential threat to his classmates last year.

Math teacher Jim Gard, who taught Cruz last year, told the Miami Herald: 'We were told last year that he wasn't allowed on campus with a backpack on him. There were problems with him last year threatening students and I guess he was asked to leave campus.'

Another student took to social media claiming Cruz had mental health issues that were 'ignored by all the adults'.

'He literally had an Instagram where he posted pictures of animals he killed gruesomely and he physically assaulted one of my friends once,' the student added.

Another student, who was not identified, but claims to know Cruz, told WSVN he was obsessed with guns and showed him pictures of them on his phone.

'He's been a troubled kid and he's always had a certain amount of issues going on. He shot guns because he felt it gave him, I guess, an exhilarating feeling.'

He added that Cruz made him nervous.

'I stayed clear of him most of the time. My time in alternate school, I did not want to be with him at all because I didn't want to cause any conflict with him because of the impression he gave off.'

He's been a troubled kid and he's always had a certain amount of issues going on. He shot guns because he felt it gave him, I guess, an exhilarating feeling. Anonymous classmate of the shooter

Former classmate Joshua Charo, 16, told the Miami Herald that all Cruz 'would talk about is guns, knives and hunting'.

'I can't say I was shocked. From past experiences, he seemed like the kind of kid who would do something like this,' Charo said.

'He used to tell me he would shoot rats with his BB gun and he wanted this kind of gun, and how he liked to always shoot for practice,' Charo added.

One student added that Cruz started selling knives out of a lunchbox when he started high school.

But Broward County School District Superintendent Robert Runcie said he did not know of any threats posed by Cruz to the school.

'Typically you see in these situations that there potentially could have been signs out there,' Runcie said. 'I would be speculating at this point if there were, but we didn't have any warnings. There weren't any phone calls or threats that we know of that were made.'

As a high school freshman, Cruz was part of the US military-sponsored Junior Reserve Officers' Training Corp program at the school.

President Trump tweeted Thursday morning, saying there were signs that the shooter was 'mentally disturbed'.

He also entreated Americans to report similar people to the authorities.

'So many signs that the Florida shooter was mentally disturbed, even expelled from school for bad and erratic behavior.

'Neighbors and classmates knew he was such a big problem. Must always report such instances to authorities, again and again!' he wrote.

Trump has cited mental health before as a cause for mass shootings, dismissing questions about gun control.

Trump spoke later in the morning about the shooting at a press conference from the White House.

Taking up the now-familiar ritual of public consolation after terrible violence, Trump spoke from the White House Diplomatic Room. In a slow, deliberate style, he sought to reassure a troubled nation as well as students' families and shooting survivors in Florida.

'We are all joined together as one American family, and your suffering is our burden also,' Trump said. 'No child, no teacher, should ever be in danger in an American school.'

Trump, who owns a private club in Palm Beach, Florida about 40 miles from the town of Parkland, where the shooting happened, said Thursday he was making plans to visit the grieving community.

He did not answer shouted questions about guns as he exited the room.

Staff and students walked single file outside the school as they evacuated after the shooting

Students were seen fleeing the building with their hands in the air, as they ran for safety from the gunman

Medical personnel tend to a bloodied victim as they help to evacuate them from the school

An injured female was transported from the school on a stretcher by first responders on Wednesday afternoon

TIMELINE OF FLORIDA SCHOOL SHOOTING 2.25pm: Gunshots ring out through the corridors of Marjory Stoneman Douglas High School in Parkland, Florida. The school goes into immediate lockdown. 2.30pm: Authorities respond to an active shooter at the school in Parkland where they say the shooter is still active. 3.pm: Hundreds of students flee the school with their hands raised as SWAT arrives to tackle the ongoing situation 3.30pm: Students and teachers begin posting harrowing footage from inside the school where they are trapped and unable to leave their classrooms. 4pm: Just after 4 p.m., Broward County Sheriff's Office announced on Twitter that a suspect had been apprehended 4.30pm: The suspect - named as Nikolas Cruz - was transported handcuffed and via ambulance to local hospital where he was placed under armed guard. Advertisement

Just before the shooting broke out at 2:25pm, some students thought they were having another fire drill.

Such an exercise had forced them to leave their classrooms hours earlier. So when the alarm went off Wednesday afternoon shortly before they were to be dismissed, they once again filed out into the hallways.

That's when police say Cruz, equipped with a gas mask, smoke grenades and multiple magazines of ammunition, opened fire with a semi-automatic weapon, killing 17 people and sending hundreds of students fleeing into the streets. It was the nation's deadliest school shooting since a gunman attacked an elementary school in Newtown, Connecticut, more than five years ago.

'Our district is in a tremendous state of grief and sorrow,' said Robert Runcie, superintendent of the school district in Parkland, about an hour's drive north of Miami. 'It is a horrible day for us.'

Police arrived at the scene to find hundreds of students fleeing the school. They later learned the shooter had concealed himself in the crowd and was among those running off the campus.

Investigators were able to identify him after trawling surveillance video. He was arrested about an hour after the shooting first broke out when police cornered him in a nearby neighborhood. He had multiple magazines of ammunition on him, authorities said.

Seventeen people were killed and more than a dozen injured.

'It's catastrophic. There really are no words,' said Broward County Sheriff Scott Israel.

A local politician told DailyMail.com that the high school has high-definition surveillance cameras that captured every single shot by Cruz and authorities are pouring through them now.

The cameras allegedly picked up Cruz walking across the empty parking lot toward the school carrying his rifle, as classes were in session.

The two school resource officers, from the Broward County Sheriff's Office, are supposed to monitor the perimeter.

DailyMail.com reached out to the sheriff's office for comment, but they did not respond.

Students released from a lockdown embrace following following a shooting at Marjory Stoneman Douglas High School in Parkland, Fla., Wednesday, Feb. 14, 2018. (John McCall/South Florida Sun-Sentinel via AP)

Students are evacuated by police from Marjory Stoneman Douglas High School in Parkland, Fla., on Wednesday, Feb. 14, 2018, after a shooter opened fire on the campus

Medical personnel tend to a victim following a shooting at Marjory Stoneman Douglas High School in Parkland, Fla., on Wednesday, Feb. 14, 2018

Medical personnel tend to a victim following a shooting at Marjory Stoneman Douglas High School in Parkland, Fla., on Wednesday, Feb. 14, 2018

Terrified students barricaded themselves in their classrooms as the shooter prowled the halls, armed with an assault rifle

Frantic parents rushed to the school to find SWAT team members and ambulances surrounding the huge campus and emergency workers who appeared to be treating the wounded on sidewalks. Students who hadn't run began leaving in a single-file line with their hands over their heads as officers urged them to evacuate quickly.

Hearing loud bangs as the shooter fired, many of the students inside hid under desks or in closets, and barricaded doors.

'We were in the corner, away from the windows,' said freshman Max Charles, who said he heard five gunshots. 'The teacher locked the door and turned off the light. I thought maybe I could die or something.'

As he was leaving the building, he saw four dead students and one dead teacher. He said he was relieved when he finally found his mother.

'I was happy that I was alive,' Max said. 'She was crying when she saw me.'

Noah Parness, a 17-year-old junior, said he and the other students calmly went outside to their fire-drill areas when he suddenly heard popping sounds.

'We saw a bunch of teachers running down the stairway, and then everybody shifted and broke into a sprint,' Parness said. 'I hopped a fence.'

Sen. Bill Nelson told CNN that Cruz had pulled the fire alarm 'so the kids would come pouring out of the classrooms into the hall.'

'And there the carnage began,' said Nelson, who said he was briefed by the FBI.

Students released from a lockdown are overcome with emotion following following a shooting at Marjory Stoneman Douglas High School in Parkland, Fla., Wednesday, Feb. 14, 2018

Parents wait for news after a reports of a shooting at Marjory Stoneman Douglas High School in Parkland, Fla., on Wednesday, Feb. 14, 2018

The scene was reminiscent of the Newtown attack, which shocked even a country numbed by the regularity of school shootings. The December 14, 2012, assault at Sandy Hook Elementary School killed 26 people: 20 first-graders and six staff members. The 20-year-old gunman, who also fatally shot his mother in her bed, then killed himself.

Not long after Wednesday's attack in Florida, Michael Nembhard was sitting in his garage on a cul-de-sac when he saw a young man in a burgundy shirt walking down the street. In an instant, a police cruiser pulled up, and officers jumped out with guns drawn.

'All I heard was 'Get on the ground! Get on the ground!'' Nembhard said. He said Cruz did as he was told.

Florida Gov. Rick Scott joined law enforcement agents near the site of the deadly school shooting on Wednesday night and offered his condolences to the victims' families and survivors.

Scott said that he couldn't imagine what the families of the victims are going through. He also said he would be visiting hospitalized survivors.

Florida Attorney General Pam Bondi said the state would cover funeral expenses for the victims and counseling for survivors.

The school will be closed for the rest of the week.

Gunshots were first heard at about 2.25pm on Wednesday before Cruz, who had escaped among fleeing students, was arrested a short time later in Coral Springs

Majory Stoneman Douglas High School is located in Parkland, west of Boca Raton, in Florida

South Florida remained on edge on Thursday. Miami's main criminal courthouse building was put on lockdown after an unspecified threat was reported, Miami-Dade County's state attorney said on Twitter.

Another Broward school briefly also went on lockdown after reports of a shooting, which turned out to be unfounded, local media reported.

A law enforcement officer is assigned to every school in the Broward County district, Marjory Stoneman Douglas High board member Donna Korn told a local newspaper. The sheriff's office also provides active shooter training and schools have a single point of entry, she said.

'We have prepared the campuses, but sometimes people still find a way to let these horrific things happen,' Korn said.

Marjory Stoneman Douglas High School is in Parkland - Florida's safest city last year.

It's also a lucrative area to live because the schools are so good.

The incident comes just a few weeks after a 15-year-old boy opened fire at his rural Kentucky high school, killing two and injuring more than two dozen others.

It's the 30th mass shooting of the year and the third-deadliest school shooting in American history, behind Sandy Hook and Virginia Tech.