Thameslink Govia says it is unable to run any services on its Thameslink and Southern routes.
Image source, Eddie MitchellRail services across Sussex, Surrey and Kent have been severely disrupted due to a major signalling fault.
A power failure in the early hours of Monday morning has caused delays and cancellations to Southern and Thameslink services.
The operator said it expected disruption between East Croydon and Brighton to continue until 12:00 GMT.
No Gatwick Express trains are running until further notice due to a points failure.
Services between Brighton and Chichester have been reduced to one train an hour and there are no Thameslink services between Cambridge and Brighton.
A Network Rail spokesperson said: “At 03:04 GMT there was a loss of power across some the UK Power Network which significantly impacted our Three Bridges Signalling Centre which controls the signalling across the majority of our Sussex route.
“All signalling was restored at 06:30 GMT and while some Southern services have resumed operating across the Sussex route, a number of Southern and Thameslink services remain significantly disrupted and there are currently no Gatwick Express services in operation until further notice.
“We’re really sorry to any passengers disrupted this morning and we encourage passengers to check with their train operator before travelling for the latest information and updates.”
Image source, Eddie Mitchell
Southern said there had been points failures at both Haywards Heath and Hove.
Passengers are being advised to allow at least an extra 60 minutes for their journeys.
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