Cruz, a 19-year-old former student, was expelled from the school last year for disciplinary reasons Broward County Sheriff Scott Israel told reporters although he could not provide details as to why.
Former schoolmate Victoria Olvera told the Associated Press Cruz was expelled last school year after a fight with his ex-girlfriend’s new boyfriend. She said Cruz had been abusive to his girlfriend.
A student at Marjory Stoneman Douglas High School said Cruz was always at odds with his teachers.
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“He would always have problems with every single one of his teachers,” Nick Hayman, a senior at Marjory Stoneman Douglas High School, told CBS News. “Every single teacher he’s ever had, there was problem.”
School officials said Cruz was attending another school in Broward County after his expulsion.
Cruz was considered a potential threat to his classmates in the past, according to his former teacher, the Miami Herald reported.
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“We were told last year that he wasn’t allowed on campus with a backpack on him,” Jim Gard told the Miami Herald. “There were problems with him last year threatening students, and I guess he was asked to leave campus.”
The math teacher told the paper he taught Cruz last year.
Another classmate, Chad Williams, also described Cruz as being troubled. He said Cruz would set off the fire alarm, day after day, and finally got expelled in the eighth grade.
More recently, Williams saw Cruz carrying several publications about guns when they ran into each other at the high school. Williams thought Cruz was there to pick up a younger sibling.
“He was crazy about guns,” Williams told Reuters, speaking by the side of the road near the high school. “He was kind of an outcast. He didn’t have many friends. He would do anything crazy for a laugh, but he was trouble.”
Dakota Mentcher, a 17-year-old junior, recalled Cruz posting on Instagram about killing animals and said he talked of doing target practice in his backyard with a pellet gun.
“He started going after one of my friends, threatening her, and I cut him off from there,” Mentcher said.
“I think everyone had in their minds if anybody was going to do it, it was going to be him,” Mentcher said.
Broward Country Schools Supt. Robert Runcie told reporters on Wednesday that he was not aware of any concerns raised about the suspect.
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“We received no warnings,” Runcie told reporters. “Potentially, there could have been signs out there. But we didn’t have any warning or phone calls or threats that were made.”
Cruz reportedly had an Instagram account which were littered with pictures of guns. It has since disappeared.
Broward County Mayor Beam Furr said during an interview with CNN that Cruz 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.
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“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 told reporters Cruz’s social media posts were being scrutinized and described some of his posts as “very, very disturbing.”
“We already began to dissect his websites and the things on social media that he was on and some of the things that came to mind are very, very disturbing,” Israel said.
Israel said the suspect had at least one AR-15 rifle as well as multiple magazines.
The attack occurred shortly before the school day ended at the high school. Hundreds of students rushed into the street after the gunman opened fire. Seventeen people were killed in the shooting.
Sen. Bill Nelson of Florida said the shooter wore a gas mask and had smoke grenades.
Nelson said the attacker “set off the fire alarm so the kids would come pouring out of the classrooms into the hall. And there the carnage began.”
He was not sure whether the gunman used the smoke grenades but assumed that’s why he wore a gas mask.
The gunman was arrested later outside, some distance from the school in an adjacent community. CNN, citing law enforcement sources, said the gunman tried to blend in with students who were fleeing the school but was spotted and taken into custody.
After the arrest, Cruz was taken to hospital to get checked out and is now being held in a secure location.
No motive has been provided for the attack which left 17 people dead and another 14 wounded.
There have been 18 shootings at U.S. schools in 2018, according to gun control group Everytown for Gun Safety.
* With files from Associated Press and Reuters