The incident took place in Riverhead around 1 p.m., Wednesday, June 1 at Riverhead High School located at 700 Harrison Ave.
The 15-year-old made the threat when police were on campus for an unrelated incident when he yelled into a classroom "I'm gonna shoot up the school," said the Riverhead Police.
The student was immediately detained by school security and was found to not be in possession of any weapons, police said.
The department's detective division responded and arrested the student who was taken to police headquarters with his parents and charged with one count of making a terroristic threat, police added.
The student was processed and transported to the Nassau County Juvenile Detention Facility where he will be detained until his arraignment on Thursday, June 2.
The student is not being identified due to his age.
A search of his home was conducted and no weapons were located, police said.
An extreme risk protection order is currently pending.
This is a developing story. Check back to Daily Voice for updates.
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