Trains between Stevenage and Peterborough are expected to be disrupted all day today (Friday, January 5) following a landslip near Arlesey railway station.
Northbound trains are not calling at Arlesey, and trains through the area may be delayed by up to 30 minutes or revised.
The landslip was first reported at 2.30pm yesterday, and is affecting an embankment on the west side of the railway.
One of the two northbound lines through Arlesey is closed as a result, and there is a "severe" speed limit of 20mph on the two lines used by northbound and southbound express trains in the area.
Northbound trains towards Arlesey cannot stop at the station. Passengers heading north and wanting to stop at Arlesey are advised to continue to Biggleswade, and change onto a southbound train.
Anybody wanting to travel north from Arlesey is advised to take a southbound train to Hitchin, and change onto a northbound train.
Passengers heading south are able to get off at Arlesey as normal.
If you have a ticket for a journey beginning or ending at Arlesey, you can use it at Letchworth Garden City or Baldock instead.
Network Rail are currently investigating options for repairing the damage. Thameslink have said that disruption is "likely to continue until at least the end of the day". They had initially expected disruption to end at 4pm on Thursday, January 4.
A Network Rail spokesperson told us this afternoon that they are hoping to fix the problem over this weekend (January 6 and 7), when there will be no trains running on the line due to planned engineering work.
They hope that by Monday morning, the line that is currently closed will be running at a reduced speed, while the other three could be back to normal.
This article was last updated at 5pm on Friday, January 5.
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