Four fire engines and around 25 firefighters were called to a fire at a flat on Draco Street in Kennington.
Most of a flat on the third floor of a five storey block was damaged by the fire. A man and a woman left the affected flat before the Brigade arrived. Firefighters rescued a man and two children from a fourth floor balcony via a turntable ladder. They were assessed on scene but there were no reports of any injuries.
The Brigade was called at 1244 and the fire was under control by 1334. Fire crews from Lambeth, Peckham and Brixton fire stations were at the scene.
The cause of the fire is under investigation.