Train delays are expected to last until 3pm between Royston and Cambridge due to overhead wire problems.
All Great Northern services between London King’s Cross to Kings Lynn are likely to be affected, with trains being delayed by up to 40 minutes. Some services have been cancelled.
A shuttle bus is currently running between Letchworth and Cambridge.
Unhappy passengers have taken to Twitter to express their annoyance.
Harry Forsyth tweeted: “Three cancelled trains in a matter of 30 minutes to King’s Cross. Instead of saying utter crap to us, tell the truth! #nothappy!”
Hugh Bateson said: “Come on then @GNRailUK why yet another cancellation? Your inability to run any sort of reliable service is simply disgraceful.”
A spokeswoman for Great Northern Railway said: “Rail replacement buses have been ordered to transport passengers between Letchworth and Cambridge, stopping at all stations.
“Ticket acceptance has also been arranged with Abellio Greater Anglia. We would like apologise for any inconvenience caused.”
You can follow this incident using the hashtag #RoystonTrains.
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