Rail services have been disrupted between Littlehampton and Worthing following an issue with the line.
Southern Rail said it experienced a fault with a set of points at Worthing earlier this morning.
Points are movable sections of track which allow trains to cross from one line to another and issue forced trains to stop running.
Services between the two station have been cancelled or delayed by up to 30 minutes.
The rail service provider said engineers attended the site and have fixed the fault.
Delays are expected to last until 1pm. Southern has apologised for the delays.
Further disruption has also been caused to rail services today following a broken down train Gatwick Airport.
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