Trains between London Liverpool Street and East Anglia are facing disruption for more than two hours after flooding caused major signal failures.
The flooding comes following a period of heavy rain across the capital and the east of England earlier today.
As a result, train services running to and from the station are facing cancellation or delays of up to 60 minutes.
Engineers from Network Rail have successfully re-opened the lines, although disruption is expected to continue until 8pm.
Stansted Express services are also facing cancellation.
The flooding could also cause trouble for Tottenham Hotspur fans heading to Colchester for the U's cup match against the north London club.
A full list of services affected is available on the Greater Anglia website.
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