Warning of 'major' train disruption due to fault
Train passengers have been facing significant disruption following a signalling system fault.
Trains between Luton and London St Pancras have been delayed, revised or cancelled following the issue that began at about 04:00 BST.
The issue was identified between Luton and St Albans, and National Rail has warned of "major disruption" until 10:00.
Railway lines reopened at 06:00 after the issue was resolved, but National Rail said due to the "large number" of impacted trains it would take a long time to restore services.
"While some services will be able to run through, service will remain disrupted and subject to change," a spokesperson added.
The below routes of Thameslink services have been affected:
- Between Bedford and Three Bridges / Brighton
- Between East Grinstead and St Pancras
- Between Orpington and Luton
- Between St Albans and Sutton
Due to the high number of services affected, National Rail was unable to offer an expected delay running time.
National Rail recommended checking online beforehand to find customer advice.
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