Around 60 fire fighters were called to an air conditioning unit that was alight on the top of a 33 storey tower block in the Canary Wharf area.
The blaze was very visible and Brigade 999 control officers received around twenty calls.
Station Manager Lee Sandy, who was at the scene, said: “While the fire was very visible, it was contained to the air conditioning unit on the roof of a commercial tower block. There were no people involved and the fire did not spread beyond the roof area.”
Eight fire engines from stations including Millwall, Shadwell, Whitechapel, East Greenwich, Dowgate, and Greenwich fire stations were at the scene.
The Brigade was called at 0039 and the fire was under control at 0158.