Eight fire engines and around 60 firefighters tackled a flat fire on Lee High Road in Lewisham.
Most of the ground floor and part of the first floor in a building of one and three floors with a shop and flats above was damaged by the fire. A number of people left the building before the Brigade arrived. There were no injuries reported.
The Brigade's control room received 17 calls about the fire.
Road closures were put in place on Lee High Road from the Junction of Belmont Park and Manor Park.
The Brigade was called at 1331 and the fire was under control at 1544. Fire crews from Eltham, East Greenwich, Bromley, Lewisham and surrounding fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.