DeKalb County fire officials are investigating a blaze at a vacant building on Clairmont Road. Officials tell FOX 5 the fire happened at a vacant house that was converted to an office on the 4000 block of Clairmont Road in Chamblee. Around six fire trucks were able to successfully put out all the hot spots and prevent any further damage. Firefighters say it's unclear whether anyone lives in the building, but they did not find anyone inside. "There's a lot of stuff that was in the attic and on the floor but we can't tell if it was being used by squatters or anyone else," DeKalb County Fire Capt. Lamar White said. Investigators believe the fire may have been set on purpose. Their investigation into the cause of the fire is ongoing.