A furnace malfunction may have caused a small fire at Black Rock Tavern in Thomaston on Monday.
Crews extinguished the fire at the 78 Main St. restaurant quickly.
Thomaston firefighters responded and called for mutual aid from Terryville to ensure the flames didn't spread through the walls.
No one was inside the restaurant at the time.
The fire marshal is investigating the cause of the fire and whether a furnace that malfunctioned a few hours earlier may have started the fire.
