Delays of up to 40 minutes on Grand Central Trains between York and Sunderland due to signalling problem at Thirsk.
Northbound lines have reopened and trains can run through the area with delays.
There is no estimate for a normal service.
Also affecting East Coast, First Transpennine Express and CrossCountry.
More top news
Do you know someone who should represent ITV Tyne Tees at the Daily Mirror Pride of Britain Awards in London?
PM announces funding will be made available for a memorial dedicated to the victims of last week’s terrorist attack in Tunisia
England beat Germany 1-0 after extra-time to finish third in the Women's World Cup.