A fire damaged a welding and fabrication shop in Kent early Thursday morning, the Puget Sound Regional Fire Authority reported.
There were no injuries to firefighters or residents.
The fire struck AAA Welding Co., a longtime business at 22610 85th Place S., near State Route 167, at 3:37 a.m., Puget Sound Fire said. But security video showed the fire may have been burning for a period of time before a passerby noticed the fire and called 911.
Heavy smoke and flames were coming from the east of the building, with reports of explosions from inside the building, as the first fire engine arrived.
Crews attacked the exterior propane tanks where the fire was burning but did not enter the building because the roof was unstable, Puget Sound Fire said. Once fire command arrived, it added a second and third alarm to bring in more crews as the fire quickly grew. Firefighters were able to knock down and bring the blaze under control within an hour.
A second business, next to the welding shop, which specializes in glass work, also was damaged.
Units from Tukwila Fire, Valley Regional Fire Authority, Renton Regional Fire and South King Fire assisted Puget Sound Fire in extinguishing the fire. King County Medic One and Zone Three Explorers provided rehabilitation services to the fire crews.
Puget Sound Fire investigators are trying to determine the cause of the fire.