Jubilee Line problems: Tube passengers led off trains
Passengers have had to be led off four Tube trains in central London after tunnel cables fell on to carriages.
Two Jubilee Line trains lost power near Bond Street station about 11:00 BST, and passengers were guided to the platform after these failed to restart.
London Underground (LU) said everybody was escorted away from the stalled trains by 12:30 BST.
Two other trains at Baker Street and Westminster were also evacuated. LU said it was investigating the cause.
It said the accident was caused by a corrosion problem on the Jubilee Line, which staff were already aware of.
"This had already been identified as a potential issue, and a work programme to tackle this had been kicked off," an LU statement said.
The improvements included a plan to ensure tunnel wall fittings and cables were safe, it added.
"I want to apologise to customers for what they had to go through this morning," said LU's chief operating officer, Howard Collins.
"We worked tirelessly to deal with the fallen wires as quickly as possible and we are tackling these issues for the long term," he added.
"We are, of course, refunding passengers who were affected and offering them compensation."