There are delays to trains on the Brighton line due to a “possible landslip".
Southern Rail announced that there was an obstruction on the line between Haywards Heath and Three Bridges at around 6.10am.
The rail operator said it would be sending a train through at a reduced speed to inspect the obstruction.
It said commuters could expect delays of around 20 minutes.
The track was checked by specialist engineers and deemed safe to run over at normal speeds at around 7.10am.
Southern Rail said that commuters should allow extra time for travel with some services still delayed.
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