PARKLAND, Fla. – Nikolas Cruz, the 19-year-old man suspected of gunning down at least 17 people Wednesday at a Parkland, Florida, high school,had once been expelled from the school for disciplinary reasons, Broward County Sheriff Scott Israel said.
The sheriff said he wasn't sure what those reasons were.
But Victoria Olvera, a 17-year-old junior, says Cruz was expelled last school year after a fight with his ex-girlfriend's new boyfriend. She said he had been abusive to his girlfriend.
"I think everyone had in their minds if anybody was going to do it, it was going to be him," she said.
Dakota Mutchler, another junior, said he used to be friends with Cruz. But he cut off the friendship as Cruz's behavior "started progressively getting a little more weird." Cruz posted on Instagram about killing animals and threatened one of Mutchler's friends, he said.
He remembered that Cruz had a pellet gun and did target practice in his backyard.
Student Daniel Huerfano said he recognized Cruz from an Instagram photo in which Cruz had posed with a gun in front of his face.
Cruz "was that weird kid that you see ... like a loner," he said.
School officials haven't confirmed such accounts, but say Cruz was attending another school in Florida's Broward County after his expulsion.
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 added without elaborating.
Hours after the gunman opened fire on students and staff near the end of the day at Marjory Stoneman Douglas High School, details began to emerge about the former student behind one of the 10 deadliest mass shootings in modern US history.
Here is what is known about the suspect so far:
'Disturbing' digital profile
Cruz was expelled from the high school for unspecified disciplinary reasons, said officials, who provided different spellings of Cruz's first name throughout the day.
Officials are examining Cruz's digital profile, which contained what Israel described as "very, very disturbing" content.
Arrested without incident
Cruz was taken into custody without incident in nearby Coral Springs after the shootings, according to Israel.
The suspect has been talking to investigators, according to a law enforcement source.
Police said Cruz was armed with multiple magazines and at least one AR-15 rifle.
Law enforcement sources told CNN the Bureau of Alcohol, Tobacco, Firearms and Explosives is tracing the.223 caliber, AR-15 firearm used in the shootings.
Suspect sought higher death toll
Investigators believe the suspect pulled the school's fire alarm to draw people out and get a higher death toll, according to a law enforcement source.
There had been a fire drill at the school earlier in the day, leading some to believe at first that the afternoon incident was another drill, a student told CNN affiliate WSVN. "Everyone just started freaking out."
"But then word started going around that it was shots and not just, like, something else, everyone just started running towards the canal," the student said.
No Threats Made
Broward County School District Superintendent Robert Runcie told reporters on Wednesday afternoon that he did not know of any threats posed by Cruz to the school.
"Typically you see in these situations that there potentially could have been signs out there," Runcie said. "I would be speculating at this point if there were, but we didn't have any warnings. There weren't any phone calls or threats that we know of that were made."
However, a teacher told The Miami Herald that Cruz may have been identified as a potential threat to other students. Jim Gard, a math teacher who said Cruz had been in his class last year, said he believes the school had sent out an email warning teachers that Cruz shouldn't be allowed on campus with a backpack.
"There were problems with him last year threatening students, and I guess he was asked to leave campus," Gard said.