Last week’s fire occurred at Bulldog Fire Apparatus, which is located at 17 Winter Street. PHOTO/JERRY SPAR

An overnight fire last week at a Winter Street company caused major damage to a Hopkinton Fire Department pumper truck that had been inside the building, Fire Chief Bill Miller said.

Hopkinton firefighters responded to a fire alarm at about 1:30 a.m. on Dec. 1 at Bulldog Fire Apparatus, located at 17 Winter Street, Miller said. There is a Hopkinton Fire Department station around the corner (on Wood Street) but Miller said that station was closed at the time.

The fire was not evident outside the building, but when firefighters entered the facility they saw smoke and discovered the truck on fire in a painting bay, Miller said. A sprinkler system helped prevent the fire from spreading, and firefighters were able to get the fire under control in about 40 minutes.

Miller said he could not comment on a potential cause for the fire as there is an active investigation underway, although he did say, “It does not look suspicious at this time.”

The pumper truck is not usable, Miller acknowledged, although he said he could not discuss specific details until the state completes its investigation. Miller added that his department also is in discussions with the town’s insurance company.