ST. GEORGE, Maine — A fire Wednesday night destroyed the main building and a 46-foot fishing vessel under construction at Clark Island Boat Works.

The fire was reported about 8 p.m. at the complex on Rein Road about 100 yards from Route 73.

Fire departments from Thomaston, Owls Head and South Thomaston assisted the St. George department in battling the flames, according to St. George Fire Chief Tim Polky.

The fire was under control within an hour, but the final crew did not leave the scene until 3:30 a.m., Polky said.

The cause of the fire had not been determined as of Thursday morning, according to the fire chief. Investigators from the state fire marshal’s office were on the scene to assist.

No injuries were reported.

The chief said he has yet to receive an estimate on the loss from the owner.

A message was left for the owner of the business, Charles Daniel “Dan” MacCaffray, on Thursday morning. A man who did not give his name was at the property and said the owner did not want anyone there. That man later parked his car across the short dirt road to prevent anyone else driving down into the boatyard.

The town has the buildings on the property assessed at $255,000.