The fire tore through the two-story building on the grounds of the Brandywine Nursing Home in Briarcliff Manor around 8 p.m.
There was no one inside at the time, and no injuries were reported. Residents of the nursing home were not disturbed since the maintenance building is located across the street.
About 75 firefighters spent almost two hour battling the flames before the fire was brought under control.
Authorities are investigating what caused the fire.
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