Train lines are blocked between Potters Bar and London this evening after a passenger was taken ill.

Railway users can expect delays on some lines between Hertfordshire and the capital, with emergency services at the scene.

"Due to passenger taken ill on a train at Potters Bar, some lines towards London are currently blocked," Thameslink confirmed.

"Emergency services are on site, and we are working to get the line clear as soon as possible.

"Services may be subject to delays and alterations. You can travel using your normal route but we'd advise allowing extra time for your journey this evening.

"If you are on a train that isn't moving, please remain on the train and listen to on board announcements for further updates."