Rail services are disrupted between Chichester and Barnham due to trespassers on the line, according to Southern Rail.
Advising its customers via Twitter, a Southern spokesperson said: "Due to trespassers on the railway between Chichester and Barnham all lines are disrupted.
"Minor delays are affecting trains running between Barnham and Chichester. You can use your normal route for travel at the moment. This is mainly affecting Southern services to and from Portsmouth or Southampton."
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