Four fire engines and around 25 firefighters tackled a fire at a shop with flats above on Stoke Newington Road in Hackney.
A launderette and dry cleaners on the ground floor of the three-storey building was partially damaged by fire. Five people were led to safety by firefighters from the first and second floor. There are no reports of any injuries.
The fire is believed to be accidental and caused by self-heating textiles.
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.
"Sometimes when materials are cleaned, put in tumble dryers and then folded and stacked, 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 0113 and the fire was under control at 0156. Crews from Stoke Newington, Islington and Homerton fire stations attended the scene.