Four fire engines and around 25 firefighters were called to a fire at a restaurant on Erith High Street.
Part of the ground floor of a restaurant below some flats was damaged by fire. Part of the internal extraction system from the ground floor to the first floor was also damaged by the blaze. There were no reports of any injuries.
The fire is believed to have been accidental and caused by a deep fat fryer in the restaurant kitchen.
A London Fire Brigade spokesperson said: “Chip pans and cooking with hot oil can be really dangerous and the risk increases when you start frying food more than once. All it can take is for you to become distracted for a few seconds and your cooking oil can quickly go up in flames.
"We'd like to remind restaurant and takeaway owners to ensure they don't have dirty ducting. If you don't clean the ducting in your extraction system regularly, you're at a greater risk of ducting fires.
"You should also make sure you keep the hob, cooker hood and extractor fan clean too – built up fat and grease can ignite and cause a fire."
The Brigade was called at 2216 and the fire was under control by 2324. Fire crews from Erith, Bexley and Plumstead fire stations attended the scene.