Four fire engines and around 25 firefighters were called to a laundrette fire on Main Road in Sidcup.
Part of the ground floor of a mid-terraced laundrette with flats above was damaged by fire. Eleven people left neighbouring properties before the Brigade arrived. There were no reports of any injuries.
The fire was discovered by passers-by who saw smoke coming from the front of the laundrette.
The Brigade’s Fire Investigators believe the fire was caused by self-heating laundry, which had been removed from a dryer before the shop closed.
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 manufacturer’s 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 0048 and the fire was under control by 0138. Fire crews from Sidcup, Eltham and Lee Green fire stations attended the scene.