A train has struck barriers at a level crossing in Billingshurst, disrupting services between Horsham and Arundel.
Southern says they are investigating after reports that barriers had been pushed onto the track.
No one has been injured and passengers on board have been led to safety.
Network Rail says the train involved in the incident damaged its shoe gear, this is the mechanism used to allow trains to draw power from the electric third rail.
Update: 11:48 - Southern says a car struck the barrier, causing it to fall onto the track.
Update: 12:30 - The line is now clear, but expect some travel disruption.
Further updates to follow on this feed....
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