Hundreds of rail passengers disembarked trains and walked along the tracks when a woman climbed onto a gantry above the line near Queenstown Road station.

Up to 500 passengers were escorted along the line to Clapham Junction station and others left trains of their own accord after being stranded in the dark for up to four hours.

Services in and out of Victoria and Waterloo stations were brought to a standstill as power to the railway lines was switched off.

Police were called to Queenstown Road railway station in Battersea to deal with the woman at about 8.10pm and she was "taken to a place of safety" at 11.20pm.

Power could not be switched on immediately because people were on the tracks but it was finally restored an hour later.

When passengers finally arrived at their destination, some were booked into hotels and others had taxis arranged for them.

Inspector Michael Blissett, from British Transport Police, said: "It took a considerable amount of time to get the service back to normal and a number of passengers, having been stuck on a train for a considerable amount of time, evacuated the train.

"The power was off and they couldn't put it on, partly because passengers evacuated the train - but they had been on there for a very long period."