Gunman Omar Mateen, 29, opened fire at Pulse nightclub in Orlando, Fla., early Sunday morning, leaving at least 49 dead and wounding 53 people.
According to a report, Mateen cheered about the horrific 9/11 attacks while he was a sophomore at Martin County High School.
Robert Zirkle, who was a freshman at the time, told the Washington Post, “He was making plane noises on the bus, acting like he was running into a building.”
“I don’t really know if he was doing it because he was being taught some of that stuff at home or just doing it for attention because he didn’t have a lot of friends,” Zirkle added.
“After 9/11 happened, he started changing and acting different,” Zirkle told the Washington Post.
Mateen’s former classmate in Stuart, Fla., told the Washington Post that he “started jumping up-and-down and cheered on the terrorists,” as other students watched the attacks happen on TV.
“It was almost like surreal how happy he was about what happened to us,” another one of Mateen’s former classmates told the Washington Post.
“Omar was saying some really rude stuff.” another classmate told the Post. “Stuff like, ‘That’s what America deserves.’ That kind of thing. It wasn’t right.”