Four fire engines and around 25 firefighters were called to a fire at an MOT testing centre on Wellington Road in East Ham.
Part of a single-storey industrial unit was damaged by fire. There were no reports of any injuries.
The Brigade’s 999 Control Officers took 23 calls to the blaze.
The Brigade was called at 2206 and the fire was under control by 2252. Fire crews from East Ham, Plaistow, Barking and Stratford fire stations attended the scene.
The Brigade’s Fire Investigators believe the fire was accidental and involved an electrical mains supply.