A "safety inspection" is causing increasing delays on services between Stevenage and London.

Thameslink has confirmed that an investigation is being carried out causing trains to run at a "reduced speed" between Stevenage and Welwyn Garden City.

A live map reveals the extent of the disruption to Thameslink and Great Northern services between Stevenage and London.A live map reveals the extent of the disruption to Thameslink and Great Northern services between Stevenage and London. (Image: Great Northern) On the company's website, it suggests there is disruption to services because of a problem with the "pantograph equipment on a train".

Pantographs are roof-mounted devices which allow trains to collect electricity from the overhead wires.

A post on X read: "Delays have now escalated meaning some services are being delayed by up to 25 minutes.

"We're working on ticket acceptance and will provide information on this shortly," the post added.

The rail company has just confirmed that tickets will now be applicable on the following services:

  • Greater Anglia services between London Liverpool Street, Hertford East (which is roughly a 20-minute walk from Hertford North) and Cambridge.
  • LNER services between Peterborough and London London Overground services between London Liverpool Street and Enfield Town, which is roughly a 10-minute walk from Enfield Chase.
  • London Underground services between Cockfosters & London terminals.

 Disruption is expected until at least 2pm.