Passengers are facing long delays after trees fell on to railway lines.
One crashed on to the tracks near Three Bridges, causing delays of up to half an hour.
Services are being held between Horsham and Three Bridges while the tree is removed. Disruption was also caused earlier after a similar incident near Crawley.
In a statement on Twitter, Govia Thameslink, which operates services on the line, said: “The line towards Horsham from Three Bridges is blocked once again by a tree blocking the railway. Services will be held whilst the tree is removed.
“To help with your journey your tickets will be accepted on Metrobus services between Gatwick Airport, Three Bridges, Crawley and Horsham.”
Passengers were earlier told that delays of up to 30 minutes would be caused by a tree falling on the line between Three Bridges and Crawley.
This tree was swiftly removed but another tree has since fallen in a similar area.
The trees may have been affected by recent adverse weather which had caused disruption across the Brighton mainline.
Trains had earlier been slowed in the Balcombe tunnel due to the weather amid ongoing repair works. Restrictions have since been lifted.
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