Thousands of homes across south London are without power after a fire at an electricity sub-station.
About 30 firefighters had to tackle the blaze which broke out at 0721 BST at the Sydenham Park Road sub-station in Forest Hill.
Two of the four transformers, located outside the building, are engulfed in flames. The power cut led to the failure of scores of traffic lights.
EDF energy said engineers are working to resolve the high-voltage power cut.
The areas affected by the power cut are Lewisham, Eltham, Sydenham, Brockley, Forest hill, Catford, Bromley, Beckenham, New Addington and Orpington.
Residents near Forest Hill have reported seeing flames and smoke.
BBC1, BBC2 and BBC London 94.9 also went off air in some parts of London at around that time.