Four fire engines and around 25 firefighters were called to a fire at a block of flats on Westwell Close in Orpington.
A small part of a five-roomed flat on the ground floor of a 10-storey block was damaged by the fire. Ten people left the premises before the arrival of the Brigade. No injuries were reported.
The Brigade's Fire Investigators believe the fire was caused by the self-heating of clothing.
A London Fire Brigade spokesperson said: "These types of fires often involve textiles that become contaminated with oil, most commonly linseed, massage and cooking oil on tea towels, tablecloths and chef whites. Make sure you check the manufacturers cleaning recommendations of your textiles before washing."
“Sometimes when materials are cleaned and put in tumble dryers, the heat from the tumble drying cannot escape. This can result in a high enough temperature allowing it to build up to a point where it smoulders and eventually ignites.
“If you are washing and then drying on a hot cycle, always use the cooling cycle on the tumble dryer so it cools down and allow the heat to dissipate properly, before stacking laundered items together.”
The Brigade was called at 0147 and the fire was under control by 0311. Fire crews from Orpington, Sidcup and Bromley fire stations were at the scene.