A trespasser on the train tracks between Potters Bar and Brookmans Park stations has caused disruption for passengers this morning.

All the lines between Welwyn Garden City and Potters Bar were closed at about 5.30am while Herts police located the person and moved them from the tracks.

Power was switched off over a large section of the line and train drivers could not leave local depots while the incident was dealt with.

The person has now been moved to safety and all lines between Stevenage and London, via Potters Bar, reopened at about 6.20am.

There will be some residual disruption until 11am - National Rail estimate Great Northern and Thameslink services could be delayed by up to 40 minutes or cancelled.