BRIGHTON, Colo. – An 18-year-old Prairie View High School student faces charges after he allegedly made threats to the school and posted threatening pictures on social media.

Frank DeFiore, 18, was arrested last Friday and faces charges of interference with staff, faculty or students of educational institutions and harassment.

According to the Brighton Police Department, a student at the school found the posts, in which DeFiore alleged he was going to shoot students at the school, on social media and reported them to school administrators.

The school then contacted police, who also found the post and further discovered “numerous weapons” in DeFiore’s possession and that he had “recently made threatening or alarming statements to multiple people,” according to the police department.

Prairie View’s principal, Jaime White, sent a letter home with students after the arrest saying the school was working with Brighton and Commerce City police in the investigation.

Former students at the school on Tuesday said that in person, DeFiore seemed like a normal student.

"I had never seen him as that type of person, I mean, he would be in class, making jokes. He would be that type of kid," said Justin McClanahan, who had a class with DeFiore last year.

But on social media, they pointed to a Twitter account for "Frank the Tank," which they believe is DeFiore.

The account includes a photo of a gun shop captioned "My Happy Place," a reference to "the voices in my head," and a recent post stating "Time for a [expletive] adventure."

Cameron Worth, a former Prairie View High Student who knows DeFiore, said that the most-threatening posts have already been deleted.

"He posted a picture of his gun he just bought, I think it was an AK or something, and he said, 'Worth every penny.' or something like that," said Worth. "I thought he just meant he was going to use it at the range and then I heard about the threats. It's really scary. My little cousins go to school here and I don't want them to get shot."

Brighton police say the investigation is open and ongoing.

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