Six fire engines and around 40 firefighters were called to a fire at a business under railway arches on Cable Street in Wapping.
Part of a railway arch unit used for rickshaw storage was damaged by the fire. There were no reports of a any injuries.
Station Commander Mark Jordan, who was at the scene, said: "The fire broke out in a business under the railway arches.
"There were no road closures in place but traffic was heavy so we advised people to avoid the area if possible.
"Trains on the DLR ran at reduced speeds."
The fire was accidental and believed to have involved lithium batteries.
The Brigade was called at 1613 and the fire was under control by 1719. Fire crews from Whitechapel, Shoreditch, Shadwell, Dockhead, Millwall and Poplar fire stations were at the scene.