Nassau County Police say 17-year-old Ryan Bernhardt was overheard making threats inside a bagel store near Massapequa High School on Tuesday.
Witnesses told police he said he "wanted to bomb the school and be a terrorist," as well as other threating comments.
He was charged with making a terrorist threat, which is a felony. It was not known if he has an attorney.
He had no weapons in his possession, nor were any found in his home.
He was scheduled to be arraigned Wednesday.
High school principal Barbara Williams posted a letter on the school website saying all threats are taken very seriously. She added Bernhardt faces school sanctions, as well as criminal charges.
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