Network Rail has confirmed there will be delays into and out of London Waterloo station until "at least 9.30am" because of signalling problems.
The station is currently experiencing delays of "up to 40 minutes", it added.
To add to commuters' misery, TfL said bus services over Waterloo Bridge were delayed by up to 20 minutes thanks to heavy traffic on Kingsway.
Passengers using services into the station complained trains had been delayed by as much as two hours, while others said they had been stuck at the station for an hour.
— Timmo (@timbo2050) May 6, 2015