Eight fire engines around 60 firefighters were called to a fire at a commercial premises on Horns Road in Ilford.
Part of a beauty salon was damaged by fire. One person has been treated at the scene by London Ambulance Service for smoke inhalation.
Road closures are in place on Horns Road and traffic disruption can be expected on surrounding roads including Ley Street and the A12 Eastern Avenue whilst the Brigade remains on scene this afternoon.
The Brigade received the first of 10 calls about the fire at 1429 and Control Officers have mobilised crews from Stratford, Woodford, Leytonstone, Romford and surrounding fire stations to the scene. The fire was brought under control by 1551.
The cause of the fire is under investigation.