ST. PETERSBURG, Fla. - Classmates. Neighbors. Teachers. Co-workers. His own brother.

Through 506 pages, they all told similar stories.

That Nikolas Cruz was mentally unstable. That he had previous issues with violence. That he liked guns. That they thought the mass shooting at Marjory Stoneman Douglas High School was a pre-planned active shooter drill. That chaos quickly ensued for those who realized it was real.

Witness statements obtained by 10News detailed a few things about the Feb. 14 massacre that left 17 people dead:

That there were warning signs

"He was just kind of just a strange kid...I could tell that he wasn't like all there," said Santiago Cuellar, 17. "He definitely had some...some problems that he was dealing with."

Cuellar, who sat next to Cruz in an engineering class their junior year, said he would look up items on school computers such as "666" and how to make a nail bomb.

Cruz even talked to him about the Pulse Nightclub shooting.

"And he goes um...I'm so glad they kill all those gay people, they really got him and I...I don't know it was just a very scary moment like I..I didn't know how to react it," he said. "I...I just shut off the conversation and minded my own business."

Zachary Davies, 17, met Cruz during their freshman year.

By sophomore year, he didn't want to be around him.

"Because like the whole thing with the dead animals in his lunchbox was just a little too much," he said. "But I didn't want to completely shut him out, cause I knew like he had guns. He can possibly be dangerous."

Cruz' younger brother, Zachary, came across text messages in his brother's phone.

“I went through his phone one day and he said, 'I’m gonna kill them,'" he said. "'I’m gonna go to that school. I’m gonna shoot everybody.' And I read it and I was like, 'wow. I should tell someone about this.' But I was like, 'he’s not serious.'”

That some thought the shooting was a pre-planned drill

A teacher in the 1200 building, whose name was redacted, initially thought the shooting was a well-planned production.

"And they were going to make this very theatrical and very true," she said. "And I...yeah so we would know how to handle all this. And when I saw kids like...on the floor and against the wall I thought man they're overdoing this. You know with fake blood coming out but they do this at (unintelligible) they have major make up and everything."

MORE: Parkland shooting survivors allege civil rights violations in lawsuit

Even with the screams, blood and gunshots, the teacher thought it was a drill.

"And then we got all the way out and I looked up and I went 'whoa you guys look how big they're doing this,' I said 'look up keep your hands up you're going to be on the news cause Stoneman Douglass the first great code red drill,'" she said. "And then when I got over on the other side..."

That's when reality set in.

"No 14-year-old kid should have to step over the bodies of their dead classmates," she said.

That Cruz easily blended into the crowd

Jack Dechene, 17, who knew Cruz since the eighth grade, saw him outside the school during the chaos.

"And I see Nick Cruz who I haven't seen in forever," he said. "I was unaware that he was like expelled from our school. I just haven't seen him in like years. So I was like dude, Nick Cruz, like what the hell. What's going on, and he just looks at me and goes - he really just looked at me and I was like so like what college are you going to man. Like what's going on. Like as I was walking passed him this was happening. And he's like oh I'm going to trade school. And I was like ahm like alright okay good for you man. And I kind of kept walking. I was like hey we should hop this fence and just keep going, just keep running and that was it."

That there was previous violence

Rocxanne DesChamps met Cruz' mother when she moved to Florida 11 years ago.

She took in Cruz after his mother died in November, but not without concern.

"He beat his mom too many times, he put the guns on his mom's head too many times and I know about this but I figured you know maybe I could control it if there's no gun around and I have my son that's bigger than him," she said.

Cruz left her home after he and DesChamps' son got into a fight.

"But then we were worried that he's coming back with that gun that he brought that he was going to go pick up the gun and kill us so for day I had to get his friend that's in the military to come here to watch over us, have a machata - machete or whatever it's called 'cuz I don't believe in gun but I had that and the baby was sleeping in my room and I have that by my bed and it's still there."

Make it easy to keep up to date with more stories like this. Download the 10 News app now.

Have a news tip? Email, visit our Facebook page or Twitter feed.