"It obviously was a prank," one officer told Daily Voice after students were dismissed and the building was emptied.
It was a small amount confined to an area of the school, so no one was injured, he said.
Taking no chances, members of Fair Lawn Rescue, the Fire Department, the Ambulance Corps and police responded.
The building was ventilated and the air quality was checked with gas meters.
Police asked that anyone with information that could help identify whoever was responsible contact them: (201) 796-1400.
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