Commuters are facing delays today after a freight train derailed between Sunderland and Hartlepool.
As a result, trains are currently not able to run between the two destinations, instead having to be diverted between Newcastle and Darlington.
Network Rail say that trains from Hartlepool towards Sunderland could be delayed by up to 15 minutes.
The disruption is expected to go on until later this afternoon at the earliest.
A statement on the National Rail Enquiries site reads: "Network Rail have advised that a freight train has derailed between Sunderland and Hartlepool.
"They are currently mobilising their specialist teams to attend and inspect the freight train.
"As a result, trains from Sunderland cannot run towards Hartlepool, but will instead divert via Newcastle and Darlington.
"Trains from Hartlepool towards Sunderland may be delayed by up to 15 minutes.
"We anticipate disruption will continue until at least 3pm."
Grand Central says that its services between Sunderland and London Kings Cross have had to be diverted and some trains will now not call at Hartlepool and Eaglescliffe.
Customers travelling with Northern Rail can use their tickets on ny service between Middlesbrough and Darlington, to connect with a CrossCountry train to Newcastle, on CrossCountry services between Newcastle and Darlington or on the Tyne & Wear Metro services between Sunderland and Newcastle.