Hundreds of passengers on the West Coast Mainline have been stranded for hours after an electric overhead cable snapped.
The cable broke on the route between Lancaster and Preston at about 08:35 GMT blocking both lines in both directions, Network Rail said.
One person tweeted they were on a train for seven-and-a-half hours, another called it “an absolute horror show”.
Stations along the route have become crowded as the delays continue.
Network Rail said that section of the line would be closed for the rest of the day.
“Our immediate focus is to fix the cables in time for start of service tomorrow,” a spokesperson said.
It earlier said the stranded passengers would be towed back to their nearest stations at about 17:00 GMT.
Virgin Trains said a rescue locomotive was sent to retrieve two trains and a third was involved in a train-to-train evacuation.
Northern and Trans Pennine Express services in the area have also been affected.
Passengers expecting to use the route have been advised not to travel, and have been warned journey times would be at least three hours longer than usual.
Simon Mabon was travelling from Macclesfield to Lancaster and said his journey – which would normally take about 90 minutes – took about eight hours.
“We got to Preston and were told the train was cancelled so we were instructed to get on to a different train and we got on to that train and we sat there for about two hours waiting because there was a broken down train in front of us,” he said.
“Then we eventually started moving and we made about 10 minutes’ progress and then it stopped and they said there were some technical issues, that there was no power, that we were stuck here for the foreseeable.”
He said after hearing that announcement at about 11:00 they were stuck on the train for more than three hours with no air conditioning and the toilets “stopped working very quickly”.
He said passengers were given a small bottle of water each but the card machine was not working in the food carriage.
Mr Mabon eventually got to Lancaster at about 15:30, where he said there was “chaos” at the station.
Phil James, director for Network Rail’s North West route, apologised for the issues.
“Our specialist electrical teams are working to repair the damaged cables. It means the railway is blocked with no trains running at present.”
Network Rail added because of the lack of electrical power in the area it had made towing back difficult.
Queues have formed at Preston station while passengers wait for rail replacement services.
There have also been queues at Oxenholme in the Lake District.
Virgin Trains said the disruption would continue until Thursday.
“We’re very sorry for the experience of customers affected by today’s disruption. We’re working closely with our partners to get customers from the affected trains to the nearest station so they can continue their journeys,” a spokesperson said.
It is not yet known what caused the damage to the 440 yards (400m) of cable.
Virgin passengers can use their tickets on Thursday, the company said.
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