Twelve fire engines and 81 firefighters and officers were called to a fire at an industrial estate in Argall Avenue, Leyton, this morning.
Most of a laundrette unit of two floors was damaged in the fire. There were no reports of any injuries.
Group Manager Simon Amos, who was at the scene, said: "Crews worked hard to bring the fire under control.
"There was quite a lot of smoke so we advised people who live in the area to keep their doors and windows closed."
The Brigade was called at 0334 and the fire was under control at 0753. Fire crews from Leyton, Walthamstow, Homerton, Stoke Newington, Tottenham and surrounding fire stations are at the scene.
The cause of the fire is under investigation.