A fire was intentionally set at an abandoned warehouse that burned for more than four hours Wednesday at the former Kings Park Psychiatric Center, authorities said.
The blaze at the abandoned complex along Old Dock Road was reported shortly before 7 a.m., police and fire officials said.
Flames burned Building 44, a vacant refrigerated storehouse, and the fire was brought under control about 11:25 a.m. after efforts by nine fire departments, fire officials said.
Arson detectives said it was intentionally set but did not give details, a Suffolk police spokeswoman said. State parks police are also investigating.
Fire officials said volunteers from Kings Park, Smithtown, St. James, Nesconset, Nissequogue, Northport, East Northport, Commack and Greenlawn responded to the scene.
A crew from Commack Ambulance also was there.