A ‘number of incidents’ are causing rail delays in West Sussex this morning (Tuesday), according to Southern.
Southern said services may be delayed, cancelled or altered between Worthing and Portsmouth Harbour.
Trains from London Victoria and from Portsmouth and Southampton will also be terminating early.
In a post on social media, a Southern spokesperson said: “Trains will be terminating at Littlehampton and Bognor Regis from London Victoria.
“Trains from Portsmouth and Southampton will be terminating at Barnham and Chichester.
“Both incidents are currently being investigated.”
Providing more information on its website, Southern added: “An issue with the brakes on a train is currently blocking the line towards Bognor Regis. An inspection of the train is required, which means both lines are currently blocked.”
Disruption is expected until 12pm.