Train passengers are being advised not to travel today after East Midlands Trains rail network ground to a halt on what is expected to be the hottest day on record.
The company is currently not able to operate any trains out of St Pancras because overhead power lines have come down trapping a train in a tunnel near West Hampstead today (Thursday, July 25).
This is on top of an already reduced service following today's unprecedented temperatures.
East Midlands Trains warned passengers this afternoon not to travel at all today because of the incident at West Hampstead that meant the entire route was blocked.
They also said that tickets were not valid for other routes but that they expected the network to be back to normal tomorrow and tickets would be able to be used then.
Speaking directly to passengers on social media, a spokeswoman said: "Please be advised due to an already amended timetable and an incident requiring emergency services near London St Pancras, services are currently not able to run our network. Please, DO NOT TRAVEL today. We are unable to get ticket acceptance via alternate routes."
An East Midlands Trains spokesman said: "We are aware one of our services has stopped near Belsize Tunnel, between West Hampstead Thameslink and Kentish Town. This is due to damage to the overhead line equipment.
"At present, we are not able to run any services south of Bedford.
"Passengers are now being taken off the train and will be picked up by replacement buses to take them into central London.
"We expect disruption to continue for the rest of the day and urge customers who have not yet set off not to travel. Tickets for today will be valid for travel tomorrow."
The company had already reduced the number of trains running today and imposed speed limits because of the soaring temperatures that it said could make the steel rails expand and buckle.
The franchise will be taken over by Abellio in August