An empty passenger train derailed just outside Brighton Station, this afternoon, bringing rail services to a halt.
Southern Rail says the train came off the tracks between the station and the depot, and at 2.3opm, all services were at a standstill.
By 4.30pm, a limited service was operating between Brighton and Lewes, Preston Park/Brighton and Worthing and north of Preston Park to and from London.
However, Southern said its trains would be disrupted for the rest of the day.
A spokesman said: “At around 2pm today, Wednesday 15 April, a Southern train derailed as it was leaving the depot at Brighton on its way to the station.
“There were no passengers on board and it was a slow-speed derailment. Power cables were damaged by the derailment, meaning no trains can run between Preston Park and Brighton until engineers can repair the cables.
“Engineers are currently on site assessing the situation.”
Tickets are being accepted on many other train and bus routes and replacement buses are now running between Haywards Heath and Brighton.
However, Thameslink services are also facing delays of about an hour, with the company saying it expects disruption to continue until at least 4pm.
At Brighton, all the ticket barriers have been closed while passengers wait for the tracks to reopen.
A empty train has derailed just outside the station. At the moment all power has been turned off hoping to get West coast back up very soon.
— Brighton Station (@brightonstation) April 15, 2015
Further updates to follow but for now I am shut. No power due to an incident all lines blocked between Patcham, here and Hove. — Brighton Station (@brightonstation) April 15, 2015
Empty train derailed at Brighton station. Good luck to any and all hoping to travel in the next hour. — Sara Barnard (@saramegan) April 15, 2015