Six fire engines and around 40 firefighters tackled a fire at a restaurant with flats above on Goresbrook Road in Dagenham.
Part of the ground floor was alight. There are currently no reports of any injuries.
Station Commander Mel Anderson, who was at the scene, said: "Crews worked swiftly to bring the fire under control and smoke has now reduced.
"Our operations are still creating some disruption in the local area, so please avoid Goresbrook Road where possible."
The Brigade’s Control Officers took the first of eight calls to the fire at 1349 and mobilised crews from Wennington, Dagenham, Barking and surrounding fire stations to the scene. The fire was under control by 1504.
The cause of the fire is under investigation.