Trains between St Albans, Luton and Bedford have been cancelled due to a fire next to the track.
The incident occurred near Luton at approximately 8.57am this morning (Friday, August 12).
Trains between St Albans City Station and Luton were immediately halted whilst emergency services responded to the blaze.
At the time, passengers were advised to allow extra time for their journeys, and tickets for Thameslink services were made available to use on East Midland Railway services, London Underground trains and the Arriva bus services 321, 100, 101 and 301.
At around 9.37am the fire had been fully extinguished, however cancellations and alterations to services continued for a time.
A spokesperson for Thameslink said: "The fire has now been extinguished and we are hoping to have lines opened very shortly.
"Once trains are able to move through the area, there will be cancellations and alterations to services, to try and reduce congestion in the area.
"Journey planners are being updated in real time, please check your journey before travelling this morning."
The National Rail Enquiries Journey Planner can be used to check rail journeys for disruption, and keep up to date with cancellations.
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