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.
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The 60-year-old takes charge of the Black Cats with immediate effect.
What has the weekend got in store for the Tyne Tees region?
The operation took around three hours to complete, with the remains being disposed of by a specialist animal by-product company.