Six fire engines and around 40 firefighters were called to a house fire on Cator Crescent in Croydon.
Most of the ground floor and part of the first floor of an end-of-terrace house were damaged by fire. Five people left the building before the Brigade arrived and one man was treated on scene.
Station Commander Matt Leaver, who was at the scene, said: “Crews arrived to find a smoke logged house and identified that the fire had originated in a cupboard under the stairs.
“The residents were asleep at the time of the fire and were awoken by smoke alarms fitted inside the property, which gave them time to escape.
“This incidents shows just how important it is to have working smoke alarms in every room where a fire can start in your home, for example any room where appliances are plugged in, plus a heat alarm in the kitchen and the bathroom.”
The Brigade was called at 2227 and the fire was under control at 2321. Fire crews from Addington, Biggin Hill and Woodside fire stations attended the scene.
The Brigade’s Fire Investigators believe the fire was accidental and caused by a faulty electrical intake.