VASSALBORO, Maine (AP) Fire investigators have concluded that a fast-moving blaze that destroyed a topless coffee shop in Maine was deliberately set.

The state fire marshal’s office made the arson determination Wednesday afternoon after investigators sifted through the rubble of the Grand View Coffee Shop in Vassalboro, north of Augusta. Officials aren’t saying how or where the fire started.

About 50 firefighters from eight communities battled the fire, which was reported just before 1 a.m. Wednesday. Owner Donald Crabtree and six others in the building escaped unharmed.

Investigators say anyone who may have witnessed the fire or activity near the scene during the early morning is asked to call the fire marshal’s arson hotline at 888-870-6162.