The 17-year-old was detained on suspicion of driving without insurance, driving otherwise than in accordance with a licence, and possession of an offensive weapon. Sergeant Mark Essam said: "I am fully aware of the issues recently around illegal bikes in the Harpenden/Wheathampstead area. "I want to reassure local officers are regularly patrolling the streets in your local areas - on foot, in marked police cars and in unmarked cars. "We will target illegal bikes and ensure we keep the streets safe." If you are able to report to police at the time the ASB is happening, please ring 101 or report through the online portal here, or ring 999 if it is an emergency.