Details emerge about Berkeley High School teen's alleged plans for shooting, bombing

The teen police say had plans to carry out a mass shooting and bombing at Berkeley High School was arrested Monday, more than a week after police found weapons parts in his home. Some people are questioning why it took so long to make an arrest. 

"It was, I think, extra shocking to know that we had been going to school for 10 days since the threat, without any of us being informed about it," said Berkeley High student Bahia Rozan.

Even though the teen is in custody, BHS students said many students and teachers were too frightened to come to the last day of school Thursday. 

"It’s pretty scary that like someone in the halls walking next to us could be capable of that," said student Danielle Mitchell.

Berkeley Police and the Berkeley Unified School District announced Wednesday that a 16-year-old student had been arrested on Monday for possessing destructive device materials and threatening to commit a crime that would result in death or great bodily injury.

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A tip to police led to a search of the teen's home eight days earlier. 

"In his residence, we found parts to an assault rifle, parts to an explosive, but not the completed items," said Byron White, public information officer for the Berkeley Police Department.

White said the threat was credible, but they couldn't arrest the teen quite yet. 

"If we don’t have probable cause to make an arrest, the person is going to get released," said White. "It takes time and space to actually put together the investigation." 

He said the school district was told the student wasn't allowed on campus.

During their investigation, police learned the teen was doing searches on the dark web, tried to buy a gun on campus, and had computer equipment that could potentially complete the weapons. 

He then turned himself in and was arrested Monday.

Students said the last day of school, where they should've been celebrating being done with finals, was clouded by the conversations about what could have happened. 

Student Ruby Carter said her teacher spoke about it in class.

"She was talking about how if they had let teachers know, at least teachers could’ve been more aware and could’ve been able to keep students in class more or be a little more careful like keep the doors closed," said Carter.

Although students were sickened by the idea that a fellow student could make plans to attack the school, they say they weren't shocked.

"Everyone says, ‘Oh, it can’t happen here.’ It can happen anywhere. It’s become very clear that it can happen anywhere, it doesn’t matter," said Carter.

Students said luckily someone tipped off police, giving detectives the time to investigate the signs, which so often we learn about after a deadly shooting.

"The biggest thing about Berkeley High, which is good, is that people are unafraid to stand up for themselves for the most part. And if they heard that something sketchy was going on, they’re going to talk about it. Because people in this school actively want their other peers to stay safe," said Carter.

White said police are still trying to piece together where the student got the pieces of the weapons he had, and what else he had planned.

"We understand the community has a lot of questions about this because it’s disturbing, concerning, horrific, all of those things put together, but this is still an active investigation," said White.

The initial tip was that the teen was trying to recruit other students to carry out the attack with him. So White said many of the witnesses investigators are interviewing and re-interviewing are juveniles.

Police are encouraging anyone else who knows something to come forward.

"If you see something, say something. If something doesn’t seem right, let somebody know about it, so we can investigate it. We are grateful that the people who came forward did so, because that allowed us to immediately intervene," said White.