PARKLAND, Fla. - The suspect in a deadly rampage at a Florida high school is a troubled teenager who posted disturbing material on social media before the shooting spree that killed at least 17 people, according to a law enforcement official and former schoolmates.
Broward County Sheriff Scott Israel said the 19-year-old suspect in the deadly school shooting, Nikolas Cruz, had been expelled from Marjory Stoneman Douglas High School for "disciplinary reasons."
Israel said he doesn't know the specifics of what happened.
But Victoria Olvera, a 17-year-old junior, said Cruz was expelled last school year after a fight with his ex-girlfriend's new boyfriend.
School officials haven't confirmed such accounts, but said Cruz was attending another school in Florida's Broward County after his expulsion.
One 17-year-old junior, Dakota Mentcher, said he used to be friends with Cruz but hadn't seen him in more than a year after his expulsion.
He said of Cruz: "He started progressively getting a little more weird."
Another student said classmates used to joke that Cruz “would be the one to shoot up the school.”
Broward County Mayor Beam Furr said during an interview with CNN that the shooter was getting treatment at a mental health clinic for a while, but that he hadn't been back to the clinic for more than a year.
"It wasn't like there wasn't concern for him," Furr said.
"We try to keep our eyes out on those kids who aren't connected. Most teachers try to steer them toward some kind of connections.In this case, we didn't find a way to connect with this kid," Furr said.
Israel said investigators were dissecting the suspect's social media posts.
"And some of the things that have come to mind are very, very disturbing," he said, but did not elaborate.
Daniel Huerfano, a student who fled Wednesday's attack, said he recognized Cruz from an Instagram photo in which Cruz posed with a gun in front of his face. Huerfano recalled Cruz as a shy student and remembered seeing him walking around with his lunch bag.
"He was that weird kid that you see ... like, a loner," he said.
The Associated Press contributed to this report.
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