Updated

Investigators say an 18-year-old Catoctin High School student was gathering materials, compiling information on school emergency procedures and planning an act of violence.

Details of the investigation were announced on Monday.

According to the Frederick County Sheriff’s Office the plot was uncovered after a concerned parent notified school officials on Thursday of a possible threat. Deputies identified the student as Nichole Cevario and immediately removed her from the classroom for transport to a hospital for an emergency evaluation.

Detectives say the student’s journal “clearly spelled out a detailed shooting event” she had planned for a day in April at the school.

According to the Sheriff’s Office, Cevario was “actively” gathering items for the plot, including a shotgun with ammunition, bomb-making materials including pipes with end caps, shrapnel, fireworks, magnesium tape, and fuse material. At no time were any weapons or explosives brought onto school property, investigators noted, and the explosive materials had not been assembled into a functioning device.

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Investigators believe she was acting alone.

“Ms. Cevario’s journal revealed that she had been planning this event for some time and had been compiling intelligence on behavior activities of the school, noting emergency procedures associated with drills conducted by school staff and obtaining intelligence on the School Resource Deputy assigned to the school,” the Frederick County Sheriff’s Office wrote in a release. “The journal was very detailed including a timeline that revealed how she was going to execute the plot and her expectations at each stage of the event.”

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