An off-duty police officer arrested a teenage moped rider just before he was about to allegedly carry out a robbery in Kingston.

Sergeant Clarke was cycling home from Kingston police station, along Tolworth Broadway, when he saw a moped with two riders being ridden in a “dangerous manner”.

He followed the suspects along the road before noticing them mount the pavement and travel along towards several pedestrians.

This is believed to be a common tactic used by criminals on mopeds as they commit snatch thefts.

After Sergeant Clarke decided to intervene he grabbed hold of the moped driver and identified himself as a police officer.

The pillion passenger fled the scene but the driver, a 15-year-old boy, was arrested as the officer sustained an injury to his leg.

Scotland Yard say the suspect was arrested on suspicion of aggravated taking and driving away, and was later taken to a south London police station.

He has since been charged with driving while disqualified from holding or obtaining a driving licence and bailed to appear at Wimbledon Magistrates’ Court on December 19.

Chief Superintendent Sally Benatar, the South West Basic Command Unit Commander, said she was “very proud” of Sergeant Clarke.

She added: “His quick reaction and intervention have undoubtedly prevented a crime from taking place.

“I command his professionalism and commitment to keeping south west London safe, even while cycling home from work.

“I’d also like to express my thanks to the members of the public who came to Steve’s assistance when they saw and heard what was happening – I’m very grateful for their support.”