
Booked: This booking photo from the Galveston County Sheriff's Office shows Dimitrios Pagourtzis, 17, who is being held on a capital murder charge stemming from Friday's deadly Santa Fe High School shooting

A cold-blooded 17-year-old high school junior burst into an art classroom at his school yelling 'Surprise!' while brandishing his father's shotgun and pistol, before opening fire and gunning down nine students and a teacher.

Dimitrios Pagourtzis was clad in a 'Born to Kill' T-shirt when he embarked on his rampage during first period at Santa Fe High School in Texas, police say.

He subsequently surrendered when confronted by police, who say he backed out of his original plan to commit suicide at the end of the massacre, but not before planting explosives around the school.

Police subsequently released a mugshot of dead-eyed Pagourtzis who is being held without bond in the Galveston County jail on charges of capital murder and aggravated assault of a peace officer.

As well as being accused of killing 10, he also injured 10 more, including John Barnes, 49, a retired Houston police officer now working as the Santa Fe resource officer who was first to confront him. He was shot in the elbow and was hospitalized in critical condition.

Officials are also questioning two other students who were detained after the shooting. They have not been named.

Police are now trying to piece together what motive 'quiet' Pagourtzis had for carrying out the shooting, the 22nd school shooting in 2018 alone.

On his now-deleted Facebook page, Pagourtzis shared a photo of a black T-shirt with the words 'Born to Kill' printed across the front on April 30. The suspect is believed to have been wearing the same shirt and combat-style boots when carrying out the massacre.

Other photos shared on Pagourtzis's page the same day in April depicted a dark-colored trenchcoat festooned with various insignia, including the Nazi Iron Cross, which the teen wrote stood for 'bravery.'

Additional patches on the garb included the rising sun, a Communist hammer and sickle pin and a depiction of the idol Baphomet, which Pagourtzis said symbolized 'Evil.'

A week prior, a photo showing a handgun and a knife appeared on an Instagram account associated with Pagourtzis. The page has since been taken down.

Students at Santa Fe High told NBC News that Pagourtzis wore a trenchcoat to school every day.

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Hero cop: Santa Fe school resource officer John Barnes, 49, pictured above with his wife, is in surgery after engaging the shooter and suffering a gunshot wound to the arm that ruptured a blood vessel

Law enforcement early in Texas identified the suspected Santa Fe school shooter on Friday afternoon as Dimitrios 'Dimitri' Pagourtzis, 17 (left and right). He is now in custody

Warning signs: On his now-deleted Facebook page, Pagourtzis on April 30 shared a photo of a black T-shirt with the words 'Born to Kill' printed across the front (left). Other photos shared on Pagourtzis's page the same day in April depicted a dark-colored trenchcoat festooned with various insignia, including the Nazi Iron Cross (right)

A photo showing a handgun and a knife appeared on an Instagram account associated with Pagourtzis in late April

Santa Fe High School in Texas was on lockdown after a shooter stormed into a class and killed 10 people Friday morning

State and federal law enforcement officers in tactical gear work outside a home in Alvin, Texas, as part of the investigation in the aftermath of Friday's deadly school shooting

A Pearland Police armored vehicle stands ready in front of Santa Fe High School in Santa Fe

Dustin Severin, 17, told KPRC-TV he saw Pagourtzis in the hallway before the shooting wearing his 'usual outfit.'

Severin says the teen has been picked on by football coaches 'for smelling bad',' and he described Pagourtzis as someone who keeps to himself.

Tristen Patterson, 16, who introduced himself as a friend of Pagourtzis', said he is interested in guns and war simulation video games, but that he has never about talked about killing people.

He also claimed that the high school junior did not show signs of bullying, but would sometimes enter the classroom 'acting a little bit down or sad. A little bit sluggish.'

A woman who answered the phone at a number associated with the Pagourtzis family declined to speak with the Associated Press.

She said: 'Give us our time right now, thank you.'

Pagourtzis plays on the Santa Fe High School junior varsity football team, and is a member of a dance squad with a local Greek Orthodox church.

Father Stelios Sitaras of Assumption of the Virgin Mary Greek Orthodox Church in Galveston, Texas, said he met Pagourtzis when the young man danced with a group as part of an annual festival in October. He said the Pagourtzises are members of a nearby parish.

Sitaras said he had never heard of the teen being in any sort of trouble.

'He is a quiet boy,' the priest said. 'You would never think he would do anything like this.'

Michael Farina, 17, said he grew up with Pagourtzis and would play video games with him. He said Pagourtzis knew a lot about guns and remembered him asking which one he should get when he was older.

'I'm kind of dumbfounded. We didn't get any warning,' Farina said.

He said a black trench coat and black boots was Pagourtzis's regular outfit to school. 'I guess you could say it was his kind of style,' Farina said. He said he wasn't someone who got into trouble and described him as a 'run of the mill' student.

Students are emotional as they gather by the Barnett Intermediate School where parents are gathering to pick up their children Friday

Police vehicles line the blocked-off street where the home of Dimitrios Pagourtzis in Alvin, Texas,

At a press conference this afternoon, Texas Governor Greg Abbott said the suspect used his father's legally owned shotgun and .38-revolver, but it’s not clear whether the father knew his son had taken them.

According to the governor, explosive devices including a molotov cocktail had been found in Pagourtzis' home in Alvin and a vehicle as well as around the school and nearby.

The governor says the suspect said he originally intended to commit suicide, as he had written in journals found on his computer and cellphone, but gave himself up and told authorities that he didn’t have the courage to take his own life.

Dr. Safi Madain at Clear Lake Regional Medical Center says six shooting victims have been treated and released. Madain says one patient remains in critical condition and the other is in fair condition. All appeared to be high school students with gunshot wounds.

Other victims have been treated at the University of Texas Medical Branch in Galveston. Dr. David Marshall, chief nursing officer, says Santa Fe school resource officer John Barnes is in stable condition Friday afternoon.

Marshall says a bullet hit Barnes’ arm, damaging the bone and a major blood vessel around his elbow. He says the blood vessel has been repaired, and that Barnes is expected to emerge from surgery within a few hours.

Houston Police Chief Art Acevedo tweeted that Barnes, who is married, was sworn in as an officer in 1995 and retired from the force this past January.

Police officers in tactical gear move through the scene at Santa Fe High School where pipe bombs were found

A man hugs a sobbing woman outside the Alamo Gym where parents wait to reunite with their children following a shooting at Santa Fe High School

Santa Fe High School junior Guadalupe Sanchez, 16, cries in the arms of her mother, Elida Sanchez, after reuniting with her at a meeting point at a nearby Alamo Gym

Santa Fe High School staff react as they gather in the parking lot of a gas station following a shooting at the school in Santa Fe, Texas, on Friday

Police officers, sheriff's deputies and ATF agents are on the scene of the active shooter situation

Medical helicopters are pictured in the parking lot of the suburban Houston school Friday

'I heard boom boom boom and my friend got shot': Harrowing accounts from inside Texas school during deadly shooting massacre that killed up to ten students Santa Fe High School student Dakota Shrader described, through tears, how she fled from the gunman who opened fire and killed up to ten of her classmates on Friday Harrowing witness accounts have emerged from inside the Texas school where up to ten students died today after a shooter opened fire in an art class. Students described the initial confusion as the fire alarm went off at Santa Fe High School before shots rang out and students fled from the school buildings into nearby streets and woodland. 'As soon as we heard the alarms, everybody just started leaving following the same procedure as [a] practice fire drill,' student Dakota Shrader told CBS News through tears. 'And next thing you know, we just hear three gunshots, loud explosions, and all the teachers are telling us to run. 'You could just hear "boom, boom, boom" so I just ran as fast as I could to the nearest forest to hide and call my mom.' The gunman, who has now been taken into custody, burst through the door of the first-period art class at around 8am and yelled 'Surprise!' before opening fire. Shrader is comforted by her mother Susan Davidson following the mass shooting at Santa Fe High School on Friday A student who saw him walking down the hallway managed to pull the fire alarm before running away. 'My friend said he saw some kid walking down the hallway with a gun so he pulled the firearm and ran out,' a senior called Tyler Turner told KTRK-TV. 'The teachers told everybody to run after three shots were heard so we all took off and ran into the trees 'Then we heard four more shots so jumped the fence into some dude's house and ran into a car wash. Tyler Turner, a senior at Santa Fe High School, said one of his friends pulled the fire alarm when he first saw the shooter walking down a corridor with a gun 'While we were sitting down trying to figure out what had just happened I saw a girl who had been shot in the kneecap.' 'I heard so many people saying there were gunshots and that people were dead,' fellow student Megan Hunter added. Another student told KTRK in a telephone interview that the gunman came into her first-period art class and started shooting. The student said she saw one girl with blood on her leg as the class evacuated the room. 'We thought it was a fire drill at first but really, the teacher said, "Start running," the student told the television station. The student said she did not get a good look at the shooter because she was running away. She said students escaped through a door at the back of the classroom. Another student, called Paige, offered up a different perspective on today's shooting. When asked by local network ABC13 if she was surprised at the massacre, the girl replied, 'No, I wasn't, it's been happening everywhere and I've always felt eventually it would happen here too.' Advertisement

Police responded to the school on State Highway 6 near Morning Glory Drive in Santa Fe just before 8am after getting reports of shots fired.

Witnesses described how the unnamed gunman burst through the door of a first-period art class and yelled 'Surprise!' before opening fire on his classmates.

Then a fire alarm was pulled somewhere in the building, sending students running into the hallway.

'As soon as the alarms went off, everybody just started running outside,' sophomore Dakota Shrader told reporters, 'and next thing you know everybody looks, and you hear boom, boom, boom, and I just ran as fast as I could to the nearest floor so I could hide, and I called my mom.'

Another student told ABC13 in an earlier phone interview that the suspect came into her first-period art class and started shooting at 7.45am.

The student says she saw one girl with blood on her leg as the class evacuated the room.

'We thought it was a fire drill at first but really, the teacher said, "Start running,”' the student told the television station.

President Trump addressed the shooting in Texas as he delivered remarks during the Prison Reform Summit at the White House in Washington

Honoring the dead: The flag flies at half-staff over the White House in honor of those who were killed and wounded in Santa Fe, Texas, Friday morning

The student said she didn’t get a good look at the shooter because she was running away. She said students escaped through a door at the back of the classroom.

Santa Fe Police, Galveston County Sheriff's Office and ATF agents responded to the school. Medical helicopters were pictured in the parking lot, along with multiple ambulances.

President Donald Trump addressed the latest school shooting in a tweet, which said in part: 'Early reports not looking good. God bless all!'

First lady Melania Trump, who is still recovering from a recent surgery, also tweeted, saying: 'my heart goes out to Santa Fe and all of Texas today.'

Trump again weighed in on the massacre in Texas as he delivered remarks during the Prison Reform Summit at the White House, expressing his 'sadness and heartbreak' and saying that his administration is closely monitoring the situation.

'This has been going on too long in our country – too many years, too many decades now,' he went on to say. 'We grieve for the terrible loss of life and send our support and love to everyone affected by this absolutely horrific attack to the students, families, teachers and personnel at Santa Fe High.

'We're with you in this tragic hour and we will be with you forever. My administration is determined to do everything in our power to protect our students, secure our schools, and to keep weapons out of the hands of those who pose a threat to themselves and to others.

'Everyone must work together at every level of government to keep our children safe. May God heal the injured, and may God comfort the wounded, and may God be with the victims and with the victims' families. Very sad day. Very, very sad.'

David Hogg, the outspoken survivor of the February 14 school shooting in Parkland, Florida, that left 17 dead, lashed out on Twitter at politicians for failing to do anything to rein in gun violence in the US.

David Hogg, the Parkland, Florida shooting survivor, addressed this latest massacre in this strongly-worded tweet Friday

Santa Fe High School student Dakota Shrader is comforted by her mother Susan Davidson

Students and staff embraced and cried after Friday's deadly shooting in Santa Fe, Texas

Students are pictured emptying their backpacks for inspection outside a row of school buses

In this image taken from video a police officer walks near school buses

School staff members sit in a school bus to be transported to another school Friday

Students are being transported to another location to reunite with their parents

News chopper footage showed a small crowd of students emptying their backpacks for inspection on the grass.

Students were transported to Alamo Gym to reunite with their parents.

Santa Fe High School has more than 1,400 students in grades 9-12. The senior class was scheduled to graduate on Sunday.

In late February, the school was briefly put on lockdown over 'popping sounds' thought to be gunshots that were heard outside. Police arrived on campus to investigate but no threat was found.

CNN reported that Santa Fe is the 22nd school shooting so far this year, and the deadliest one since Parkland.