Six fire engines and around 40 firefighters responded to a fire on Casson Square in Lambeth.
The fire occurred in the basement of a residential block of 34 floors. An electrical intake cupboard in the basement was completely destroyed by fire. There were no reports of any injuries.
The Brigade was notified about the fire at 2046 and the incident was under control by 2156. Crews from Lambeth, Soho, Dowgate and surrounding fire stations attended the scene.
The fire is believed to have been accidental, caused by an electrical fault.