A spokesman for the firm said: “We’re sorry to say a person has been hit by a train between Croydon and Purley and we’ve had to close all lines through the area.
“This means no trains can run to/from London from Gatwick and Sussex, and we advise passengers to delay their journeys until at least after 11am.”
Southern rail said the lines are blocked while the emergency services work to deal with the incident.
A spokesman added: “We strongly advise to avoid travel if you can.”
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