Passengers on a packed train were evacuated after being stuck for more than an hour because of a power failure.
The London Overground service left Queens Road Peckham in south-east London at 8.35am on Friday, but slowed and stopped shortly afterwards, and most of the lights went out.
Commuters and other passengers sitting and standing on the train were told there was a loss of power, and that they would be evacuated coach by coach.
Passengers said the driver gave regular updates and opened windows.
London Overground said electrical supply problems between Shadwell and Surrey Quays were disrupting services on the East London Line.
Trains are suspended on the entire route between Highbury & Islington and West Croydon / Crystal Palace / New Cross / Clapham Junction.