A teenage boy was stabbed in front of his mother by a knife-wielding thug on a Boris bike.
The pair were walking in Hackney, east London, at about 9.45pm when three youths surrounded them following a verbal 'altercation'.
A fourth male, on the Barclays hire bike – nicknamed after London Mayor Boris Johnson - then rode up behind the 16-year-old and stabbed him in the back before the group ran off.
The victim was taken to hospital where he was treated for a single stab wound before being discharged.
The suspect riding the bike was a black male, about 17-years-old, tall and slim. He was wearing a dark tracksuit with the hood pulled up.
Police have appealed for witnesses to the incident on November 19.