Thomas Matthew Crooks threatened to ‘shoot up’ high school classmates years before Trump assassination attempt

Would-be Trump assassin Thomas Matthew Crooks threatened to “shoot up” his high school five years before he put the ex-president in his crosshairs — a detail criminologists say may offer a clue into the motive behind the assassination attempt.

The future killer’s warning was enough to keep dozens of Bethel Park High School students home for the day, but the incident was dismissed by school officials at the time, his former classmates recalled.

“We had like this anonymous place you could post things or tell on someone on our computers at school and he posted something like ‘Don’t come to school tomorrow,’ and something else that made it sound like he’d put bombs in the cafeteria bathrooms,” Vincent Taormina, 20, told the DailyMail.

“Half of us just didn’t come to school the next day – I didn’t. But it wasn’t taken seriously.

“We all texted one another and it came out pretty quickly that it was Thomas and his friend group who’d made the threats to shoot [the school] up.”

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The then-glazed-over threats are now a focus of the FBI investigation into Crooks — especially considering how closely the plan mirrors the attack he launched at the Trump campaign rally over the weekend.

Crooks squeezed off up to seven gunshots from the roof of a building in an apparent attempt to assassinate Trump. He instead killed a married dad of two and seriously injured two others in the audience. Trump suffered only a grazed ear.

Investigators later found explosive devices in Crooks’ car , which was parked not far from the grounds where the rally took place.

Crooks was just 15 years old when he allegedly made the threats in 2019 — the same year his image was noticeably absent from the high school’s yearbook.

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During that time, the gunman was “relentlessly” bullied by his peers, who described him as a loner and teasingly nicknamed him “the school shooter.”

He was also barred from joining extracurricular social clubs, including the school’s rifle team , classmates said.

The endless teasing and isolation may have played a part in his decision to open fire at the Pennsylvania rally, according to one criminologist.

“Thomas Crooks, the shooter in this case, has or has experienced major depression disorder. That fits quite in line with the pathway to violence on a threat assessment,” Dr. John Cencich, a professor and criminologist at Penn West University, told WXPI.

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“We can see it’s been reported by his classmates that he was bullied almost daily, that he sat alone, he said very little.

“This is what is important, that he tried out for the rifle team, and not only did he not make it, but he was also told to not come back. That must have been very devastating to him.”

Despite being out of high school for two years and having been admitted to both the University of Pittsburgh and Robert Morris University for the fall semester, Crooks may still have been harboring ill feelings toward his old bullies, Cencich said.

Crooks perfected his shooting skills in the months before his attack and set his sights on a big target to show his classmates what he could do — much like how John Hinckley tried to assassinate Ronald Reagan to impress actress Jodi Foster, the criminologist said.

“The grievance is not directed towards former President Donald Trump but towards his classmates, what does he do in the meantime, he joins a gun club to try to improve his shooting skills,” Cencich said.

Investigators are still pouring through Crooks’ phone and devices for a clue into his motive, but have so far turned up nothing.

He researched Trump’s movements before he shot him and also looked up President Biden, the FBI said.

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