Nichole Cevario's father told officials the teen posed a threat to student safety.
A teenage girl in Maryland has been accused of plotting a mass shooting at her high school that she anticipated would end with her own death, police said.
The suspect, 18-year-old honor roll student Nichole Cevario, was immediately pulled from class Thursday after her father warned officials at Catoctin High School in Thurmont that she was a threat to student safety.
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After questioning the teen, investigators determined she also posed a threat to her own safety and she was taken to a hospital to be treated for mental health issues.
Authorities say Cevario had been plotting and amassing supplies for months (Frederick County Sheriff's Office)
Authorities also searched the teen's home, where they reportedly discovered evidence Cevario had been planning the assault, and amassing materials to help bring it into reality, for months.
The Frederick County Sheriff's Office said in a statement that Cevario’s journal "clearly spelled out a detailed shooting event that she planned to execute on a specific date in April at Catoctin High School."
"Evidence recovered from her home revealed that she was actively acquiring materials needed to execute the plot. Those items included a shotgun with ammunition, bomb making materials to include pipes with end caps, shrapnel, fireworks, magnesium tape, and fuse material," the statement said.
At a press conference held Monday, Frederick County Sheriff Charles Jenkins was frank as he described how it felt to read the teen's journal of her planning for the alleged plot, which began with an entry on December 16, 2016.
"It shocks the conscience to see that someone of that age could be thinking like this," Jenkins said. "For some time [Cevario] 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."
Cops say items found at Cevario's home included bomb making materials, shrapnel, fireworks, magnesium tape, and fuse material
Authorities obtained an arrest warrant for Cevario that will be served upon her release from Frederick Memorial Hospital, charging her with 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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In a video posted to YouTube, Frederick County Public Schools Superintendent Dr. Terry Alban called Cevario's parents "courageous" for coming forward.
"Whenever you hear or see anything that raises concern, you need to trust us and come to us so that we can do the right thing and handle it just like we did in this case," Alban said. "Those relationships, that trust, that's what enables the policies and the procedures that we have put in place to keep our school safe work. And they did."
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