Electrical supply problems between Wandsworth Common and Clapham Junction are causing delays and cancellations across Sussex this morning.
Southern have said passengers can expect delays of 60 minutes to trains between Balham and London Victoria until at least 10.30am.
Gatwick Express services are currently unable to run and trains heading to the south coast via Horsham are currently facing serious delays.
Tickets are being accepted across the public transport network. Passengers may use: London Buses on any reasonable route; London Overground services on any reasonable route; London Underground services on any reasonable route; Southeastern services between Tonbridge / Beckenham Junction and London; South West Trains services between Portsmouth/Epsom/Dorking and London; Thameslink services between Sutton/Brighton and London; First Great Western services between Redhill and Guildford.
To keep up to date with the disruption go to the National Rail website.
Passengers can also follow the #ClaphamJunction on Twitter.
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