East Coast rail chaos: Network Rail blames faulty components
Faulty components on power lines are being blamed for bringing chaos to rail travel through Hertfordshire and Cambridgeshire over the last fortnight.
Network Rail said it had identified the components that had failed in incidents at Radlett and at St Neots.
In an apology to passengers, the firm said further work was being done to minimise the chance of repeat failures.
Thousands of commuters and football fans had seriously disrupted journeys due to both incidents.
About 200 passengers, believed to be mostly football fans returning from games in London, were stranded overnight at King's Cross.
Other travellers were subjected to train delays, cancellations and bus journeys.'We are sorry'
One group going north were put on a bus that was later involved in an accident at Huntingdon.
They were further delayed but no-one was injured.
Network Rail said: "Our initial investigations into the recent overhead power supply incidents at Radlett and St Neots indicate that both incidents were caused by component failures.
"We are sorry for this and for the disruption many passengers will have experienced as a result.
"In both instances we have identified exactly which components failed and we are carrying out further work to establish the reasons so that we can minimise the chance of repeat failures in the future."
The firm said it continuously monitors track, signalling, overhead power supply and other equipment for ageing and degradation.
"While of little comfort to those whose journeys were delayed or disrupted by these recent incidents, it's important to note that since April 2011, the number of overhead lines faults causing delays to passengers has fallen by 14%, with the number of serious incidents down by 23%.
"At both Radlett and St Neots, our programme of maintenance checks had been carried out as planned and all inspections were up to date."