(PARKLAND, Fla.) -- Students, parents and faculty at Florida’s Marjory Stoneman Douglas High School today struggled to fathom why a former student allegedly opened fire there Wednesday, killing 17, as law enforcement officials searched for clues.
Student Dakota Mutchler, 17, said he knew something was wrong when the school carried out two fire drills back-to-back.
"Everyone started lining up in the field like they were supposed to, and then you started seeing kids running," the junior student told ABC News. "It became clear that it was no longer a drill. It was the real thing."
Authorities arrested 19-year-old Nikolas Cruz, who had been expelled from Marjory Stoneman over disciplinary problems, in the aftermath of what has become the deadliest school shooting since an attack on an elementary school in Newtown, Connecticut, in 2012.
The suspect slipped away from the Parkland, Florida, high school campus by blending in with other students who were trying to escape, police said. Cruz was eventually apprehended in Coral Springs, just outside Parkland and about 30 miles northwest of Fort Lauderdale.
Cruz had an AR-15-style rifle that had apparently been legally purchased, according to a law enforcement official briefed of the investigation.
Mutchler said he knew the suspect but had stopped speaking to him when Cruz began to display violence toward others.
Cruz would often post videos on social media of his killing or harming animals, Mutchler said, adding that the suspect also threatened a female friend of his once.
"Everyone in school, like those that knew him, speculated about him," Mutchler continued. "He got suspended a lot of times and he sold knives in his lunch boxes and he was expelled, but no one expected him to come back and shoot. He started progressively getting a little more weird and I kind of cut off from him because I felt like he was a bad influence on me."
The suspect tried adding Mutchler on Snapchat a few weeks ago, but he "just declined it because I didn't want to talk to him."
Others students on the scene who knew Cruz described him as someone with a penchant for weapons and violence and that he'd talked about having "target practice in his backyard" with a pellet gun.
"He was in my class in seventh grade," Gabrielle Pupo, a survivor of the attack, told reporters Wednesday night. "I knew he wasn't OK when he punched the window in and said, 'I'm gonna cause karma one day,' because he got in trouble with the teacher."
Pupo said she saw Cruz shoot a faculty member and coach at the school, Aaron Feis.
"I heard the shots, and then I saw the shooter run after Mr. Feis, and I saw Mr. Feis get shot," Pupo said. "Today he tried blending into the crowd and was talking to one of my friends as he was exiting."
"He was very focused on what he was doing," she added.
Cruz was booked into the Broward County Jail and charged with 17 counts of pre-meditated murder.
Students and parents were still close to the scene at the large high school several hours after the shooting, waiting for updates from police. Some were seen kneeling and crying while others held pictures of missing classmates.
Victoria Olvera, a 17-year-old senior, said she was also looking for two friends who went missing after the tragedy.
"We called her family and they don't know either," Olvera said, holding up a picture of a "close friend" believed to be in the freshman building when the shooting happened. "It's not real. It doesn’t feel real at all.”
Witnesses reported a barrage of gunfire around 2:40 p.m., near dismissal time. Video posted on social media showed students were fleeing from the shooting with their hands in the air. One student said he had to climb a fence to escape.
"My teacher thought it was a firecracker, but then a gunshot went off again, so I started running out of my class," a student, who only gave his first name, Amar, said in an Instagram post. He said his teacher tried to usher him back into the classroom, but he was afraid of getting trapped in the building.
"I couldn't. I had to go," he said. "I jumped the gate as quick as I can."
Survivors of the shooting have flooded social media with images from the scene, with some sharing video from inside classrooms as teachers and faculty tried to keep students calm amid sounds of rapid gunfire.
The school will be closed the rest of the week, and grief counselors will be made available for students beginning this morning, officials said.
The FBI has encouraged anyone with potentially useful pictures or videos of the incident to upload them online.
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