Delays of up to 30 minutes on East Coast between Kings Cross and Doncaster due to signalling problem at Peterborough.
Mainly affecting northbound services.
Trains are running at reduced speed through the affected area, resulting in delays.
There is no estimate for a normal service.
More top news
The constituency of Washington and Sunderland West includes the UK's largest car plant, which was opened by Nissan in 1984.
This seat was formed prior to the 2010 General Election, taking in Sunderland city centre and the Ryhope area to the south.
The constituency of Stockton South includes relatively affluent areas like Yarm and Eaglescliffe.