All lines are blocked between Horsham and Arundel after a person was hit by a train.
Southern Rail are urging people to delay their journeys amid severe disruption to services.
In a statement, a spokesman said: “It is with great sadness that we report a person has been hit by a train between Horsham and Arundel.
“All lines are blocked between these stations whilst the emergency services work to deal with this incident.
“Please delay travelling until later today if you can.
“If you need to travel now, your journey will take much longer than usual.
“Rail replacement buses have been requested to run across the area and we’ll provide an update once we have confirmation.”
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