Chatham fire fighters responded Thursday afternoon to a report of a fire in a building at 184 Commerce Park North.
Arriving at the scene, firefighters could hear explosions from what is thought to be propane tanks and called in a second alarm, bringing assistance from fire departments in Orleans, Harwich and Brewster.
The cause of the fire has not been definitely determined, but reports indicate a man working at the site had removed a gas tank from a truck before leaving the building for more than an hour.
Fire officials say it took a couple of hours to knock down the fire and then do overhaul to insure there were no hot spots remaining.
There were no injuries reported.