Four fire engines and around 25 firefighters were called to a fire at a shop on Green Street in Forest Gate.
Half of a storage area at the rear of the shop was damaged by fire. There were no reports of any injuries.
The Brigade was called at 2355 and the fire was under control by 0116. Fire crews from Stratford, Plaistow, East Ham and Leytonstone fire stations attended the incident.
The fire is believed to be accidental and was caused by a halogen floodlight setting fire to stored items and the insulation of a commercial fridge.