A faculty member pulled the fire alarm in response to several people reporting breathing problems around 10 a.m. Thursday morning, Parsippany Police Chief Andrew Miller said.
The room was ventilated and all students and faculty were allowed to reenter the building shortly after.
It was not clear why the student sprayed pepper spray. The investigation remained ongoing as of Friday evening.
The Mount Tabor Fire Department, Par-Troy EMS and Detective Sgt. L. Costigan responded to the scene.
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