Delays of up to 40 minutes on East Coast between Leeds and Skipton due to emergency services dealing with an incident at Micklefield.
There is no current estimate for when a normal service will resume.
Also affecting CrossCountry, First TransPennine Express and Northern Rail services.
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Police carrying out a drugs raid in Stockton found a cannabis farm with plants valued in excess of £60,000.
No one was understood to be injured in the incident and the reason for the engine failure is currently unknown.
A look ahead at the forecast for the Tyne Tees region.