Railway trespasser caused major train disruption through Welwyn Garden City and Stevenage

A Great Northern train

A Great Northern train - Credit: Archant

Trespassers caused serious disruption for Great Northern train services through Welwyn Garden City (WGC) and Stevenage this evening.

A passenger on the 6.47pm Ely to London Kings Cross train raised the alarm because someone had got out of the carriage onto the railway lines.

All routes between WGC and Alexandra Palace were shut while Herts police and Network Rail searched the area.

It has all now been reopened, but until the end of service, there may still be half an hour delays between Stevenage and London Kings Cross.