Northern confirmed on its Twitter account on Monday, July 29, that a signalling fault on the line between Hartlepool and Seaton Carew is preventing services running between Newcastle and Middlesbrough in both directions.
As a result, trains in the area will face delays or could be cancelled, the service said.
The disruption is expected to last until around 3pm at present, with no estimate for when Network Rail’s repairs will finish.
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Customers have been advised that Northern tickets are being accepted on Metro services between Newcastle and Sunderland.
Replacement road transport, operated by Compass Royston, will be provided between Sunderland and Middlesbrough.
It is expected that these bus will begin arriving from 11.30am.
Passengers on platforms are being urged to listen for announcements in their station, or consult the customer information screens for the latest running information.