Commuters travelling to and from London Kings Cross have confronted extreme disruption after signalling failed twice exterior the station.
Traces have been shut when a significant fault was adopted by one other after the signalling had first been restored in the course of the morning rush hour.
Community Rail apologised and stated the issue had been triggered when the ability provide to the indicators failed.
Two rail corporations earlier warned passengers to keep away from journey if doable.
Nice Northern and Thameslink urged prospects to not make any journeys in the course of the morning until "completely needed".
Community Rail's East Coast Predominant Line director Paul Rutter stated groups have been investigating what had occurred and "early suggestions from the positioning signifies that the engineering work carried out over the weekend could have been concerned".
"I understand how necessary a dependable practice service is to passengers and freight. I'm sincerely sorry for the disruption we triggered," he added.
Nationwide Rail Enquiries stated that disruption on Nice Northern and Thameslink trains was anticipated till about 17:00, with some cancellations and delays.
Grand Central, Hull Trains and LNER had additionally been hit by the issue however are not affected.