BALTIMORE (WJZ) — An 18-year-old student has been arrested after authorities found that she was planning a shooting plot at a Maryland school.

Nichole Cevario faces charges of possession of explosive material with intent to create a destructive device and possession of incendiary material with the intent to create a destructive device.

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WJZ’s Amy Yensi was told that her parents discovered the plan and immediately told the school, possibly saving many lives.

It could have been deadly and devastating, as investigators say, Cevario was actively planning and plotting a mass shooting at her school.

Authorities found she had been stockpiling ideas, a shotgun, and explosive materials to target students. Cevario purchased the gun and materials legally.

Catoctin High School officials were warned on Thursday about the plan by Cevario’s father, who discovered the possibly deadly evidence in their Thurmont home.

“It’s just weird to think someone you’ve known, you don’t actually know,” said student Madie Forrest.

Investigators found a diary detailing the plot. The diary did not reveal specific targets or bullying, but reveals the young suspect is struggling with mental health issues.

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“Sheriff’s office investigators determined early on that Nichole posed a threat not only to the school, the student body, but also to herself,” said Frederick County Sheriff Charles Jenkins.

According to investigators, Cevario was the only person involved in this plot, and had been planning the shooting for some time. She had a date picked out, April 5, and even had a detailed timeline of everything that would happen.

They also discovered the fireworks and pipes had not been combined into a bomb which was part of the plan.

“Just from my encounters with her, she was a positive and happy person like anyone else would be, which is another reason why it doesn’t make sense in my head,” said Forrest.

Cevario was immediately removed from her classroom and submitted to Frederick Memorial Hospital for emergency evaluation. She is still in the hospital, but as soon as she is released from the hospital, she will be officially charged.

“There’s no doubt in our minds that we averted a disaster.”

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