Four fire engines attended a fire at a restaurant and office block on Cork Street in Mayfair, this afternoon.
Around 120 people – 20 from the affected building and 100 people from the neighbouring premises - evacuated before the Brigade arrived at the scene.
The fire affected the restaurant's extraction system and the ducting between the basement and first floor was complexly damaged in the blaze.
London Fire Brigade spokesperson said:
"Businesses should make sure their extraction system is kept clean as a build-up of fat and grease within the filters can lead to a fire.”
Firefighters from Lambeth, Kensington and Chelsea fire stations were at the scene.
The Brigade was called at 1402 and the fire was under control at 1541. The cause of the fire is under investigation.