Extra passengers could be on Aylesbury-bound rail services this evening, after London Euston Station had to be evacuated.
No trains are running in or out of Euston due to a line-side fire near South Hampstead which has damaged signalling equipment.
Network Rail has engineers on site trying to restore services as soon as possible.
However, as a result of the fire the power supply to Euston station was temporarily cut, leading to the evacuation of the station.
Train services running from Euston to the West Midlands and North West will be cancelled, delayed or revised, and passengers are being advised to use alternative routes where possible including on the Chiltern Mainline.