Disruption on Grand Central Trains between Sunderland and Kings Cross, and between Bradford Interchange and Kings Cross due to overhead line problems at St Neots.
Tickets are being accepted on East Midlands Trains services.
Trains are not able to run between Peterborough and London, disruption will be ongoing for the whole of today.
A replacement bus service is running between Peterborough and London.
Also affecting First Capital Connect, East Coast and First Hull Trains.
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