P.S. 15 in Paterson was evacuated Wednesday due to a small fire, which has been deemed suspicious.

Firefighters say when they arrived at the school they believed the fire was deliberately set in three separate areas of the building. The fire department also called in the deputy sheriff?s office and the bomb squad to investigate after firefighters found a written letter posing as a bomb threat.

P.S. 15 students were housed at P.S. 24, the New Roberto Clemente School, after the evacuation.

The bomb squad found no active devices in the building. Officials say an arson investigation is now underway.

Meanwhile, the school superintendent is assuring parents that despite the recent fire code issues in the district, P.S. 15 had no violations and passed its inspection.