Passengers are facing continued disruption at a busy London railway station after a train derailed when it ran a red signal.
No trains ran in to or out of Paddington station on Thursday evening and just half are expected to run this morning.
There were no passengers on board during the derailment, which Network Rail said happened when the train went through a red signal.
A spokesman for Network Rail said: "An empty train travelled past a red signal outside Paddington station which activated an automatic derailment."
Overhead line equipment was damaged and trains are able to access only three of the six lines serving the station.
The operator has apologised to customers for delays and advised customers to use routes through Waterloo and Marylebone as an alternative.
Tickets not used on Thursday will be valid for Friday and Saturday.
A Great Western Railway (GWR) spokesman said: "We're sorry for the disruption this incident has caused to customers this evening. We are working with Network Rail to get things back to normal as safely and quickly as possible, however train services are likely to be affected tomorrow morning due to the extent of damage caused by the derailment.
"At the moment, we expect to be able to run around half our normal service into and out of Paddington on Friday morning. We hope this will improve as further progress is made and we would ask customers to check before travelling. Passengers should expect GWR and alternative trains to be much busier than usual, particularly with additional people travelling to Ascot."
The Network Rail spokesman added: "Our engineers are working around-the-clock to repair significant damage caused by this incident. We are working to get things back to normal as quickly as possible and to minimise the inconvenience for passengers."
One passenger tweeted a picture of empty departure screens at Paddington, while others described their frustration at delays.
Tanbir tweeted: "stuck on the train into #londonpaddington going to miss an event I've paid for, really annoyed!"
Clive Nunn wrote: "Won't make it to the concert now. Gutted."
Arabel Bailey ?said her journey home took five hours as a result of the cancellations.
She wrote: "5 hours, 2 Ubers, 4 new friends and I've finally made it home after a derailment closed #londonpaddington."
Heathrow Express services were suspended due to a loss of power at the station following the derailment.