Nassau County police charged 18-year-old Joshua Barley of Garden City with making a terroristic threat.
Police say the incident occurred at 8:15 a.m. Wednesday at Rosemary Kennedy Boces School in Wantagh. They say a witness reported that Barley wrote on the blackboard that he wanted to "assassinate the principal and take over the school."
The principal was informed and notified police.
Barley was to be arraigned Thursday in First District Court in Hempstead. It wasn't immediately known if he had a lawyer.
Last week, another Nassau high school received a threatening message. Police say a former Mepham High School student allegedly told someone he wanted to shoot everyone at the school.
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