Rail services between Stevenage and Welwyn North were delayed on all lines this morning after a trespassing incident at Knebworth.

Transport police were called to Knebworth station at 7.05am after a person allegedly got on the tracks.

“Officers attended and arrested a 20-year-old man on suspicion of trespass,” said a British Transport Police spokesman.

“He is currently in custody and helping officers with enquiries.” Delays of up to a quarter of an hour were caused. Great Northern Line reported soon after 8.30am that services were returning to normal.