Four fire engines and around 20 firefighters and officers were called to a fire at a church in City Road in Shoreditch.
Part of an electrical intake room in the basement of the church was damaged by fire.
Approximately 300 people left the church before the arrival of the Brigade.
The Brigade was called at 1230 and the fire was under control at 1404. Fire crews from Shoreditch, Dowgate, Islington and Bethnal Green fire stations attended the scene.
The cause of the fire is believed to be accidental and due to a fault in a fuse box.