Thousands of train passengers could face severe delays until the end of the week - after "extensive" damage to overhead power cables.
The problems at Radlett in Hertfordshire mean services run by three train companies - Southeastern, East Midlands Trains and First Capital Connect (FCC) - are likely to be affected throughout today.
People could be delayed by up to an hour as there's major disruption expected on services between Luton and St Pancras International in London.
More top news
City Hall has warned that Londoners should avoid coming to the centre of the capital on New Year's Eve unless you have a ticket.
Members of the Queen's Guard have been assigned the protection of armed police, amid reports they could be targeted by terrorists.
When Robin Ollington wrote to Buckingham Palace suggesting they introduce a Christmas tree, he didn't expect them to write back...