Six fire engines and around 40 firefighters tackled a shop fire on High Street North in East Ham.
Half of the ground floor of the shop was damaged by fire. The remainder of the ground floor suffered smoke damaged. There were no reported injuries.
Fire investigators believe a failure within a fluorescent strip light to be the cause of the fire.
The Brigade was called at 1942 and the fire was under control by 2103. Fire crews from Ilford, East Ham, Stratford, Leyton and Barking fire stations attended the scene.