Trains are being disrupted between Horsham and Barnham (Image: Newsquest)
SOME trains are not able to run due to a "suspected track defect".
Trains are not running from Horsham to Barnham, while trains going the other direction are able to run at a reduced speed.
Network Rail engineers are at the site inspecting the track defect.
A Southern Rail spokesman said: "Services between Victoria and Bognor Regis/Portsmouth (via Horsham) are disrupted.
"We can't run between Horsham & Barnham in the Portsmouth/Bognor direction.
"We can still run from Barnham towards Horsham, but only at a reduced speed."
Services from Victoria to Bognor/Portsmouth are being diverted via Hove currently.
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