There are no trains running between Brighton and Lewes until at least midday because of structural damage to a viaduct in Brighton.
Train operator Southern said: “Structural damage to the London Road viaduct was discovered during overnight engineering work.
“Network Rail and structural engineers are attending to the viaduct to investigate and begin repairs.
“While this is ongoing, no trains can run on this route until further notice.”
Southern also said: “Urgent repairs to the track between Brighton and Lewes means all lines are blocked.
“As a result, trains are unable to run between these stations and will be cancelled, delayed or revised.
“Services that usually run between Brighton and Seaford will run between Lewes and Seaford only and will be reduced to one train per hour in each direction
“Services that usually run between Brighton and Eastbourne / Ore will be diverted between Brighton and Lewes via Haywards Heath.
“Delays of up to 30 minutes are possible as a result and these services will no longer stop at London Road, Moulsecoomb or Falmer.
“This applies to services running in both directions
“If you are travelling to or from one of these stations, you will need to use one of the alternatives below to reach your destination.
“Rail replacement buses have been confirmed and will be in both directions between Lewes and Brighton, calling at all stations in between.
“Timings will be as follows. Buses from Brighton to Lewes will depart at 15 and 45 minutes past the hour.
“Buses from Lewes to Brighton will depart on the hour and at 30 minutes past the hour.
“Please note that capacity will be limited and it is still advised to use local Brighton and Hove bus routes where possible.
“You can use your ticket to travel at no extra cost on Southern or Thameslink services to or from Brighton, including via Haywards Heath.”
Tickets are also valid on Brighton and Hove Buses on routes between Brighton, Lewes, Seaford and Eastbourne.
Acceptable routes include the 12, 12A and 12 X, 28, 29, 29B and 29X and the 25.
Southern added: “Please check journey planners and station information boards before you travel and allow extra time to reach your destination.
“You may be entitled to compensation if you experience a delay in completing your journey today.
“Please keep your train ticket and make a note of your journey as both will be required to support any claim.”
