Disruption around Cambridge started on Tuesday evening and is expected until Wednesday afternoon
Train passengers were stranded on trains and at stations for several hours hours after overhead electric wires were damaged.
The problem began shortly before 7pm on Tuesday near Cambridge, leading to several lines serving the city being blocked.
Operator Great Northern released a photograph showing a pantograph – a device mounted on train roofs to collect electricity from wires – on the ground next to a train.
Another image shows loose electric wires draped over the side of a train.
The firm said the power was switched off.
British Transport Police said it assisted Network Rail in “evacuating passengers from several stranded trains”, working with operators Great Northern, CrossCountry and Greater Anglia.
Passenger Colin Chang sent a tweet to Greater Anglia at 10.54pm which read: “Was meant to get back to Cambridge North at 18:58 but now having to get an Uber to get there.
“Being stuck on the train for 3+ hours with bad communication is not a great look. I’ve already filed for compensation but I’m not optimistic. Ruined my day.”
Another frustrated traveller, named Lee, wrote a message to CrossCountry stating: “Can you please explain why, given that I’ve been sat on your train from Stansted to Birmingham for over three hours when it should’ve arrived at my destination almost two hours ago, I haven’t been offered the alternative of a taxi to my destination?”
The firm replied that taxis were waiting at Cambridge for passengers on his train to take them to their destinations.
Ben Connor sent a tweet to Great Northern which read: “Is there any information on when more than one or two taxis, or a bus will be arriving at Royston.
“Have been here for 1.5 hours trying to get to Cambridge, there are dozens of people here stranded.”
A Greater Anglia spokeswoman said: “We apologise for the disruption on our West Anglia route last night. This was due to significant damage to the overhead wires in the Cambridge area.
“The incident happened at around 7pm, and as result, trains were unable to run through the affected area.
“Two of our services – the 5.13pm London Liverpool Street to Cambridge and the 5.37pm London Liverpool Street to Cambridge North – were safely evacuated and alternative arrangements made so passengers could complete their journeys. Neither train was full.
“Network Rail engineers worked through the night to repair the damage and services started to run from 9am today.
“We are very sorry for the disruption caused to passengers. Anyone who was affected by the delays can claim delay repay at www.greateranglia.co.uk/delayrepay.”
Journeys continued to be affected on Wednesday, with disruption not expected to end until 1pm.
Published: by Radio NewsHub