
A series of photos shows the devastating scene left after Omar Mateen opened fire inside an Orlando gay night club killing 49 innocent people and injuring dozens more.

Mateen, who became the worst mass shooter in American history, shot more than 100 people with an AR-15 assault rifle and handgun on the dance floor at Pulse night club early Sunday morning.

Investigators are examining evidence at Pulse nightclub in an attempt to uncover exactly what happened at the nightclub.

Sunday night, workers were removing bodies four at a time on stretchers out of the club and loaded them into white vans. The action was repeated over and over until all of the bodies were removed and taken to the County Medical Examiner's office.

On Monday, officials said they had identified 48 of the 49 victims, and are working to inform their families. Once their families have been informed, the names will be released online. So far, 36 of those names have been released.

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Police forensic investigators work at the crime scene of a mass shooting, as bodies are removed at the Pulse gay night club in Orlando, Florida, on June 12, 2016

Investigators work the scene following a mass shooting at the Pulse gay nightclub in Orlando Florida, U.S. June 12, 2016

Overnight on Sunday, dozens of bodies were pulled from the bullet-ridden Orlando nightclub four at a time

On Monday, officials said they had identified 48 of the 49 victims, and are working to inform their families

Workers on the scene were grim-faced as they worked through the night on Sunday to remove the bodies from the Pulse nightclub

Grim task: Law enforcement officials have erected forensic tents at the Pulse gay nightclub where Omar Mateen killed at least 49 people on June 13 in Orlando, Florida

Tragedy: The scene at the Orlando mass shooting that killed at least 49 people and injuring 53 others at the Pulse nightclub

Investigation: Police forensics investigators work at the crime scene of a mass shooting at the Pulse gay night club in Orlando on June 12. At least 49 people were killed when Omar Mateen opened fire inside

Three forensic investigators are pictured above working the crime scene as the windows at the nightclub are completely broken out

The broken windows at the gay night club are pictured above as investigators work the tragic scene

Investigators from the office of the medical examiner investigate on the west side of Pulse nightclub, as bullet holes and large holes can be found throughout the building

Mateen's ex-wife said he was unstable and physically abusive. He had a son with another woman, Noor Zahi Salman (left), who was listed as his wife on a 2013 mortgage and appears to have left him

Pictured: US citizen Omar Mateen, 29, the suspected Islamic extremist who slaughtered at least 49 people inside a gay club in Orlando early Sunday morning

PULSE KILLER 'SHOT DEAD AS HE EMERGED THROUGH HOLE IN WALL' Police officers crashed an armoured vehicle into a wall of US nightclub Pulse in a desperate bid to save hostages. Gunman Mateen was killed when he crawled through the wall firing his weapons at waiting officers. John Mina, chief of police at the City of Orlando Police Department, told how his officers handled the tense standoff with the terrorist who carried out the worst mass shooting in US history. Mateen shot some of his initial victims at the Orlando club before taking the rest hostage. He barricaded himself in a toilet with around four or five hostages and called 911. FBI Director James Comey added in a statement on Monday that the shooter was involved in precisely three calls to a 911 dispatcher at approximately 2:30am. Comey said: 'He (Mateen) called and hung up. He called again and spoke with the dispatcher and hung up. 'And the dispatcher called him back and they spoke briefly. 'During the calls he said he was doing this for the leader of ISIS, who he named, and pledged loyalty to. But he also appeared to claim solidarity with the perpetrators of the Boston Marathon bombings and solidarity with the Florida man who died as a suicideb bomber in Syria for Al-Nusra Front - a group in conflict with the so-called Islamic State. 'The Boston bombers and the suicide bomber from Florida were not inspired by ISIS, which adds a little bit to the confusion about his motives', Comey concluded. Police chiefs chose to act when he boasted to the 911 call handler about ‘bomb vests, explosives’ and said he would murder more young people. Officers first laid explosives on the wall to create a space which those held hostage could escape through. Officers then drove the vehicle at speed crashing into the wall when the first plan failed. Mateen then wriggled out of the hole and fired before he was shot down. Police said the action saved the lives of dozens of people. Advertisement

Thirty-nine of the dead were killed at the club, and 11 people died at hospitals, Orlando Mayor Buddy Dyer said.

Jon Alamo had been dancing at the Pulse for hours when he wandered into the club's main room just in time to see the gunman. "You ever seen how Marine guys hold big weapons, shooting from left to right? That's how he was shooting at people," he said.

'My first thought was, oh my God, I'm going to die," Alamo said. "I was praying to God that I would live to see another day.'

Mateen, who purchased the weapons legally, had been investigated by the FBI three times but the bureau did not take further action.

Concerns about homophobic remarks he made whilst at work did not stop him from being employed as a security guard at G4S for nine years.

The company offers security advice and personnel to countries around the world and also secures some US nuclear sites.

The gunman exchanged fire with an officer working around the club at 2am before going back inside, according to Orlando Police Chief John Minia.

Writing on Facebook, Pulse, which described itself as the most prominent gay club in Orlando, urged party-goers to 'get out and keep running' as bullets started to fly.

There were about 320 people inside the club at the time of the shootings and about 100 people were taken hostage.

'He had an automatic rifle, so nobody stood a chance,' said Jackie Smith, who saw two friends next to her get shot. 'I just tried to get out of there.'

At 2:09 a.m., Pulse posted on its Facebook page: "Everyone get out of Pulse and keep running."

Mateen went on to exchange gunfire with 14 police officers at the club, and took hostages at one point. In addition to the assault rifle, the shooter also had a handgun and some sort of 'suspicious device,' Police Chief John Mina.

About 5 a.m., authorities sent in a SWAT team to rescue the remaining club-goers, Mina said.

At first, officers mistakenly thought the gunman had strapped explosives to the dead after a bomb robot sent back images of a battery part next to a body, Mayor Dyer said. The robot was sent in after SWAT team members put explosive charges on a wall and an armored vehicle knocked it down in an effort to rescue hostages.

Nine hero officers used a 'controlled explosion' to distract the shooter before fatally shooting him and were able to rescue about 30 hostages who were hiding in the bathroom of the club.

During the gunfire, an officer was shot, but he was saved by his helmet. It was thought that at least one hostage had been locked in a bathroom with gunshot wounds.

Mayor Buddy Dyer said in a press conference: 'Many were saved by the heroic efforts of the men and women of the OPD, the Orange County Sheriffs, Seminal County Sheriff's office.'

At around 6am local time police tweeted: 'Pulse Shooting: The shooter inside the club is dead.'

Local and federal authorities are tasked with what is expected to be a lengthy investigation into the shooting.

Photos taken both on the ground and overhead show forensic investigators at the scene working to piece together exactly what happened, as huge holes can been seen left in the walls.

Authorities said on Sunday that Mateen, who was from Port St Lucie in Florida, was quizzed three times by the FBI for terror links and concerns.

The shooter, who had no criminal history, was licensed to work as an armed security guard in Florida, law enforcement sources said.

An FBI spokesman said at a press conference later in the day that Mateen purchased multiple guns in the past few days.

The spokesman said that the investigations by the FBI were closed and that's why the 29-year-old gunman was able to purchase the weapons.

The federal agency said Mateen was first interviewed in 2013 after he made 'inflammatory remarks' to a colleague.

'The FBI first became aware of Mateen in 2013 as he made inflammatory comments to coworkers, alleging possible terrorist ties,' Ron Hopper an FBI special agent said during a press conference.

The 2013 investigation came after he told his co-workers he knew the Tsaranev brothers who were responsible for the Boston bombing.

MATEEN WAS 'DISTRESSED' WHEN HE BOUGHT ST LUCIE PROPERTY IN 2013 Further details about Mateen's property arrangements have come to light. Police officers have removed evidence from 519 and 937 south-west Bayshore Boulevard, St Lucie. The four and three-bed homes are a four minute drive between each other. Mateen was said to be in a 'distressed' state when he bought number 937 for $95,000 in September 2013. Today it is thought to be worth about $190,000. The Palm Beach Post reported that he took out a $76,000 loan to finance the home. It was advertised as a 'spacious pool home' which needs 'a little TLC'. The second home at 519 was bought for $160,000 in 2010, having been built two years earlier. His father Mir Seddique, also known as Seddique Mateen, has his company The Durand Jirga, registered at 519. It has 10 rooms and is built over two stories and is worth about $250,000. Advertisement

Federal and local law enforcement remove evidence from two Treasure Coast homes that are linked to Orlando nightclub shooter, 29-year-old Omar Mateen

Mateen's name was registered at two homes in Orlando which police raided on Sunday for evidence as their investigation continues

Edward Sotomayor Jr. (left) and Stanley Almodovar III (right) were the first victims identified in the aftermath of the worst mass shooting in American history

Police forensic investigators work at the crime scene of a mass shooting at the Pulse gay night club in Orlando

Police forensic investigators examine large holes on the side of the building which holds Pulse nightclub

Police forensic investigators work at the crime scene on Sunday after 49 people were killed at the Orlando club

COLLEAGUES COMPLAINED ABOUT MATEEN'S 'FREQUENT' RACIST AND HOMOPHOBIC COMMENTS AND SAID HE WAS 'UNHINGED' Mateen led what many would consider a normal life: he was married, had a child and worked as a security guard. But he was really an 'unhinged' extremist who regularly made homophobic and racist remarks at work. That's the account of former police officer Daniel Gilroy who worked alongside Mateen, 29, for security firm G4S. Gilroy said he complained to bosses but they did nothing because of Mateen's Muslim faith. 'I quit because everything he said was toxic,' Gilroy told Florida Today. '...and the company wouldn't do anything. This guy was unhinged and unstable. He talked of killing people.' Gilroy said Mateen would take over from him on shift at PGA Village between 2014-15. Mateen began stalking him, sent up to 30 messages and made around 15 calls to him a day, Gilroy added. Advertisement

Investigators are facing a difficult task, as 49 people were killed inside the club during the shooting

The inside of Pulse night club appears to be heavily damaged as glass from broken windows is likely inside

FBI agents investigate the severely damaged rear wall of the Pulse Nightclub after the shooting on Sunday

FBI agents investigate the damaged rear wall of the Pulse Nightclub in what is the deadliest mass shooting in American history

AR-15 RIFLE MATEEN CARRIED HAS OFTEN BEEN USED IN MASS SHOOTINGS IN US HISTORY The AR-15 rifle is the civilian model of the M-16 and is capable of firing a large number of rounds in seconds The type of AR-15 rifle that terrorist Omar Mateen used to kill 49 people and wound dozens more at the nightclub in Orlando has become the weapon of choice for mass murderers in the U.S. and is one of the common links between the shootings. Even though it has caused carnage and left dozens of people dead in multiple shootings this decade alone, the military-inspired semi-automatic rifle designed for civilian use is perfectly legal in most states. There were calls for a nationwide ban after the same type of firearm - capable of firing dozens of rounds in less than a minute without being reloaded - was used in the Sandy Hook school shooting, but it remains readily available at gun shops and was purchased just last week by Mateen before he went on his killing spree. The AR-15 rifle is the civilian model of the M-16 and is capable of firing a large number of rounds in seconds Mateen, 29, was armed with a .223-caliber AR-15-type rifle and a 9mm semi-automatic pistol – both legally purchased – when he opened fire at the Pulse gay club in Orlando early Sunday morning. Called a ‘killing machine’ or 'weapon of war' by those who want to see it banned, the AR-15 rifle is the civilian version of the fully-automatic M16 used by soldiers in the Vietnam War. Unlike the M16, users must pull the trigger every time they want to fire a shot. The most common versions of the AR-15 have been banned in a handful of states, including California. When it is used against humans it is intended to cause maximum carnage in a brief amount of time, said experts. Advertisement

'The FBI thoroughly investigated the matter including interviews of witnesses, physical surveillance and records checks.

'In the course of that investigation, Mateen was interviewed twice.'Ultimately we were unable to verify the substance of his comments, and the investigation was closed.'

In 2014, Mateen came to the FBI's attention again and agents interviewed him about a potential connection he may have had with American suicide bomber Moner Abu Salha, who lived about 30 minutes away in Vero Beach, Florida.

'We determined that contact was minimal and didn't to constitute a substantive relationship or threat at that that time,' Hopper said.

In addition, the Bureau of Alcohol, Tobacco and Firearms said that Mateen purchased two weapons legally within the last week.

'He is not a prohibitive person so he can legally walk into a gun dealership,' the representative from the ATF said. 'He did so within the last week or so.'

FBI agents investigate near the damaged rear wall of the nightclub on Sunday afternoon

Large holes were left in the brick wall at the rear of the nightclub after the horrific shooting

'He's a known quantity,' another source said. 'He's been on the radar before.'

Global security firm, G4S, confirmed that he worked for the company since 2007.

'We are shocked and saddened by the tragic event that occurred at the Orlando nightclub,' a statement by the company reads.

'We can confirm that Omar Mateen had been employed with G4S since September 10, 2007. We are cooperating fully with all law enforcement authorities, including the FBI, as they conduct their investigation.

'Our thoughts and prayers are with all of the friends, families and people affected by this unspeakable tragedy.'

An FBI spokesman said Sunday's mass shooting is being investigated as an act of terrorism, adding that they are looking into whether it was an act of domestic or international terror, and if the Mateen was a lone wolf.

The FBI believe Mateen, who was shot dead by officers, may have 'leanings to radical Islamic terrorism'.

A group of authorities stand near the rear of the nightclub as they conduct an investigation into the shooting

But his father, Mir Seddique, told NBC News his son became angry when he saw two men kissing in Miami several months ago.

'This has nothing to do with religion,' he said. 'We are saying we are apologizing for the whole incident. We weren't aware of any action he is taking. We are in shock like the whole country.'

Twitter accounts which claim to be affiliated to the Islamic State have hailed the shooting, although DailyMail.com cannot confirm whether the terror group was behind the attack.

Mateen, a Muslim and father to a three-year-old son, was born in 1986 in New York and married Sitora Alisherzoda Yusufiy, who was born in Uzbekistan, in 2009.

His father told NBC News: 'We were in Downtown Miami, Bayside, people were playing music. And he saw two men kissing each other in front of his wife and kid and he got very angry.'

'They were kissing each other and touching each other and he said, 'Look at that. In front of my son they are doing that'. And then we were in the men's bathroom and men were kissing each other.'

Investigators take photos and examine the outside scene of the shooting at Pulse nightclub in Florida

Seddique said Mateen attended Indian River State College, as well as having an associates degree in criminal justice.

Manteen had a Statewide Firearms License and was trained in firearms, according to Fox News.

Hopper said Mateen made 'threats in the past that he has ties to terrorist organizations'.

Police were at his apartment in Port St. Lucie this morning. Ken Mascara, Sheriff of Port St. Lucie County, told DailyMail.com: 'We have sealed the apartment where Mateen was living. The FBI is bringing bomb diffusing equipment.'

Since the news of the horrific shooting emerged, celebrities and politicians are calling for stricter gun control laws.

President Obama furthered his gun control message today when addressing the massacre in Orlando.

'Although it's still early in the investigation we know enough to say that this was an act of terror and an act of hate,' Obama said, making no reference to ISIS or Islamic terror in his brief remarks.

Obama called the shooting spree, at the gay nightclub Pulse during Pride month in the United States, a reminder of how easy it is for someone to get a hold of a weapon that could kill people in a 'school, or a house of worship, or a movie theater, or in a nightclub.'

The forensic investigators dressed in white jumpsuits with covers over their shoes in order to not contaminate the tragic scene

Dozens of police and emergency personal have surrounded the area around the nightclub in Orlando as the investigation continues

'And we have to decide if that's the kind of country we want to be,' Obama said.

'And to actively do nothing is a decision as well,' the president added.

Both Donald Trump and Hillary Clinton took to Twitter on Sunday morning to give their initial reactions to what's now being called the most deadly shooting in United States history.

'Woke up to hear the devastating news from FL. As we wait for more information, my thoughts are with those affected by this horrific act,' Clinton wrote on Twitter, signing it with her trademark 'H' to show that the message was actually penned by the Democratic candidate.

In a statement made by her campaign later, Clinton also called for gun control.

'This is the deadliest mass shooting in the history of the United States and it reminds us once more that weapons of war have no place on our streets,' Clinton said.

Trump made Twitter followers aware of the shooting, then went back to attacking Clinton – this time for a new general election ad – before penning another tweet about the tragedy in Orlando, in which a gunman entered a gay nightclub and mowed down 49 people, with another 53 left injured.

'Appreciate the congrats for being right on radical Islamic terrorism, I don't want congrats, I want toughness & vigilance. We must be smart!' Trump later wrote.

It appears the street where the nightclub is on is completely closed as police and federal authorities investigate the incident