Six fire engines and around 40 firefighters were called to a fire in a car park on Thurlow Street, Walworth.
A pile of rubbish in parking area was destroyed by fire.
The fire caused lots of visible smoke and the Brigade’s 999 control officers took 19 calls to the fire.
Three children were treated at the scene for smoke inhalation and taken to hospital by London Ambulance Service crews as a precaution.
The Brigade was called at 1659 and the fire was under control at 1848. Fire crews from Old Kent Road, Peckham, Dockhead, Brixton, Lambeth and Shadwell fire stations attended the scene.
The cause of the fire is under investigation.