The overhead wires on the East Coast Main Line are used to power some trains and when there is damage to the equipment, a section of the line is closed to allow essential safety inspections to take place.
Some trains have now resumed but disruption is expected for the rest of the day between Newcastle and Berwick. Trains are being cancelled or delayed and some bus replacement services are in place.
Passengers who need to travel are strongly advised to check their journey via National Rail Enquiries or with their train operator and allow plenty of time.
Network Rail engineers are carrying out vital repairs overnight to allow services to resume tomorrow morning.
Paul Rutter, route director for Network Rail’s East Coast route, said: “I apologise for the disruption that passengers on the East Coast Main Line are experiencing today as a result of the damage to the overhead wires.
“The safety of passengers and our teams is our main priority and we had to close a section of the line to complete safety inspections. We’ve managed to get some trains moving and work will take place tonight to repair the damage.
“I want to thank passengers for their patience and advise those who need to travel to check before they do so.”
Passengers are also reminded that there are no trains to or from London King’s Cross this afternoon, tomorrow or on Sunday. Network Rail is completing the final stage of work to transform the track layout as part of the £1.2billion East Coast upgrade.