Soon after 2.30pm yesterday damage was found to overhead power cables on three lines around Hitchin. This damage was confined to the wire itself and not the structures, but was significant enough that we had to stop traffic through the area.
By 6.30pm we had two lines through Hitchin open allowing limited services to run. The route to Cambridge remained blocked, although passengers from London were and are able to reach the town via Liverpool Street.
From 1am to 5.30am we had just one line open through the affected area, with diversions via Hertford, while the damaged wire was replaced.
We handed the line back at 6.3am and when the first train went through at 6.54am, further damage was found.
The nature of the damage means we have had to close all lines through Hitchin and we are continuing to repair the problem and investigate the cause.
Network Rail would like to apologise for the disruption to people's journeys during this period and we are working hard to fix the problem.
Please do check with your train operator before travelling as there are diversions in place.
More top news
Scotland Yard said the male youths will appear in custody at Westminster Magistrates' Court on Saturday.
The family of Oliver Dearlove urged people to "think again" before using their fists, as the man who killed him began a six-year jail term.
London Fire Brigade took Southwark Council to court on four charges in relation to safety breaches at Lakanal House in Camberwell.