Fire damaged an automotive repair garage in Donovans Industrial Park in Mount Pearl late Saturday night.
St. John's Regional Fire Department crews responded at 11:12 p.m. to Capital Collision Centre on Sagona Avenue.
Platoon Chief Brian Tucker told CBC News firefighters found heavy smoke when they arrived, and had to force their way into the building.
He said once they were inside, they could see flames from the furnace room, located at the rear east of the building.
Tucker said the furnace room sustained significant damage, while the rest of the building has smoke and water damage.
Crews were able to knock down flames within 15 minutes, Tucker said. He added it took another hour to ensure all signs of smoke had been extinguished.
The fire is now under investigation.