Four fire engines and 21 firefighters and officers were called to a fire at a block of flats in London Road, Croydon.
The communal area and a flat on the lower ground floor were destroyed by fire. Seven people left the building before the arrival of the Brigade.
The Brigade was called at 0033 and the fire was under control at 0131. Fire crews from Norbury, Croydon, and Woodside fire stations attended the scene.
The cause of the fire is believed to be a fault with a capacitor in the fridge.