Commuters have been urged not to travel to London after a power shortage caused dozens of trains to be cancelled, with Southern Rail particularly affected.
London Victoria station in particular has been affected, with crowds and disruption hitting one of the capital’s largest hubs.
Network Rail has said the cancellations and delays are expected until the end of the day due to a total loss of signalling power on three separate supplies in the Streatham area.
The company advised passengers not to use those operators for travel from the south into the capital.
The problem with signalling equipment was discovered at 10.30pm on Wednesday and Network Rail engineers have been unable to fix it despite working overnight.
The cause of the fault has been traced to the failure of the power supply linked to signalling equipment.
Around 210,000 passengers use London Victoria each day. Southeastern services to the station appeared unaffected.
The issues have also affected Thameslink services between Luton and Wimbledon, which have been suspended until further notice.
Rail bosses are attempting to arrange replacement buses to operate at “key locations”, but these will be “subject to availability” as many are already in use to take children to school.
A Network Rail spokesman said: “Owing to a loss of signalling at Streatham Common, services are being disrupted to and from London Victoria.
“The signal loss means we are unable to run services between Balham, Selhurst and Haydons Road.
“We have had engineers working on site overnight doing all they can to fix the problem. However, we anticipate that the signalling will not be up and running this morning.
“We apologise for the inconvenience caused by the fault and passengers are being advised not to travel with Thameslink, Southern or Gatwick Express from the south into London this morning.”
Commuters have spoken of their disappointment as they face a day of severe delays.
One wrote: “When every train, and connecting train to work is cancelled, and you have to pay half a day’s wage just to get to work on time.. @TLRailUK you better be picking up this bill… @Uber save the day with another wonderful driver!”
Another fumed: “Every single train to Victoria cancelled and all services to London Bridge delayed. After last night’s issues, you’ve really done us proud. Congrats on being a total embarrassment!”
And another said: “Are you serious @TLRailUK every single train cancelled between 06:00 and 09:00 this morning!! Are you going to provide a taxi for me to get to work??”
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