Signalling problems at Eaglescliffe causing delays of up to 30 minutes on First Transpennine Express between Northallerton and Middlesbrough.
Also causing delays of up to 30 minutes on Grand Central Trains between Northallerton and Sunderland, and on Northern Rail between Darlington and Saltburn.
There is currently no estimate for when a normal service will resume.
More top news
Blaydon MP Dave Anderson has backed his under-fire leader Jeremy Corbyn after 172 MPs gave him a vote of no confidence
Motorists are being warned that the A1 will be fully closed tonight as repairs continue after a sinkhole opened up in Gateshead
The Yorkshire Dales National Park is extending its boundaries to include part of Lancashire and a larger part of Cumbria