A man wearing a gas mask and armed with an AR-15 rifle entered his former Florida high school on Valentine’s Day, unleashing a hail of bullets that left at least 17 people dead and more than a dozen wounded. The victims, according to authorities, included students and staff.

The shooting began around 2:30 p.m. at Marjory Stoneman Douglas High School in Parkland, a small city about 15 miles southwest of Boca Raton. Police said the gunman pulled a fire alarm before starting his rampage, prompting the some of the school’s nearly 3,000 students and staff to stream into hallways and stairwells. Some students sought cover inside the school once the shooting began. Videos posted on social media show children hiding in closets an under desks, surrounded by the blasts of gunfire and screams. Others show bodies strewn on classroom floors.

“It’s catastrophic,” said Broward County Sheriff Scott Israel, during a news conference hours after the shooting. “There really are no words.”

The shooter, a former student who had been expelled, was taken into custody without incident.

Here’s what we know, and don’t know, about what happened:

The shooter was a former student, who had been expelled

Police identified the shooter as Nikolas Cruz, 19. The New York Times reports that Cruz had was a former student of Marjory Stoneman who had been expelled.

Cruz’s former teachers and classmates described him as a troubled teen with disciplinary issues and an obsession with weapons.

Jim Gard, a math teacher at the high school, told the Miami Herald that the administration had warned teachers about Cruz.

“We were told last year that he wasn’t allowed on campus with a backpack on him,” Gard told reporters. “There were problems with him last year threatening students, and I guess he was asked to leave campus.”

Broward County Mayor Beam Furr told CNN that Cruz had received treatment at a local mental health clinic. Furr said Cruz had not been to the clinic for more than a year.

According to the Washington Post, Cruz was adopted. His father, Roger Cruz, died of a heart attack several years ago. His mother, Lydia, died last November of pneumonia.  

After his mother’s death, Cruz moved in with a friend’s family, said Jim Lewis, a lawyer representing the family.

Lewis said the family believed Cruz was depressed, but did not prove a threat.

“The family brought him into their home,” Lewis told The Post. “They didn’t see anything that would suggest any violence. He was depressed, maybe a little quirky. But they never saw anything violent.

According to a report from Buzzfeed News, a YouTuber reported a comment left on one of his videos by a user named Nikolas Cruz that stated “”I’m going to be a professional school shooter.”

In a press conference, Rob Lasky of the FBI said that in 2017, the agency was alerted to the comment. The FBI conducted “database reviews and checks” but were unable to identify the person who made the statement, he said.

Cruz confessed to the shooting, reports the AP. During police interrogation, he also told law enforcement officials that he left behind his AR-15 and a vest he was wearing so he could blend in with the evacuating crowd.

Students described moments of confusion and terror

Students thought it was weird when they heard second fire alarm of the day — they’d already had a drill that morning. They quickly realized that this time, something was seriously wrong. They then unknowingly split into two groups — those who got out, and those who stayed. The students let out of the building jumped fences and ran with their arms above their heads. The ones on lockdown barricaded themselves in classrooms and closets.

Students used their phones to document the fear and chaos. One described being “f-cking scared.”

https://twitter.com/TheCaptainAidan/status/963865696643026944

Another girl, down on the floor, wrote that she was shaking, capturing a picture of her Valentine’s Day-themed socks.

For a few hours, students became reporters. Senior David Hogg, a TV production student, used his video camera to interview his classmates while hiding in a small classroom, according to the Sun Sentinel.

After being held inside for around two hours, the students on lockdown began to be dismissed. The girl with hearts on her socks let out a whimper of relief. In another classroom, a SWAT team entered to find dozens of students on the floor, their arms in the air. One student’s hands shook violently in fear.

Florida has lenient gun ownership laws

Florida has a Child Access Prevention Law, which requires gun owners to store loaded weapons securely if they know that a minor might access them. Violation of the statute can result in a misdemeanor or a felony, depending on what the child does with the gun.

One study estimated Florida’s adult gun ownership rate at 32.5 percent in 2013 – slightly higher than the national average. The state had a firearm death rate of 13.12 per 100,000 people in 2016, placing it 24th in the country.

The state does not require background checks for private sales, nor does it require firearm owners or purchasers to be licensed.

Parkland is one of the state’s safest cities

Last year, Parkland was ranked the safest city in Florida in a report produced by the National Council for Home Safety and Security, a home security trade association. The ranking, which relied on FBI data, put Parkland’s violent crime rate at 0.24 per 1,000 residents – less than a tenth of the national average. The city of 29,242 people saw only seven violent crimes in 2016.

There have already been more than a dozen school shootings in 2018

So far this year, there have been 13 instances in which a gun was discharged on the grounds of an American elementary or secondary schools, resulting in five deaths and 19 injuries, according to Gun Violence Archive. That toll does not include the incident in Parkland.

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