Police are urging a "legend" who stuck out his foot to trip up a suspected drug dealer they were pursuing to get in touch so they can thank him.
In CCTV footage released by Kingston Police the unidentified passer-by can be seen walking arm-in-arm with a woman when he spots police chasing the teenage offender who was suspected of selling Class A drugs.
The man, dressed smartly in a jacket and shirt, then casually trips the suspect who falls to the ground, allowing police to arrest him.
Kingston police later tweeted the video, and thanked the member of the public, who simply walks off with barely a backward glance, after assisting officers with the arrest.
On Tuesday PC Sebastian Ellis from Kingston Borough told the Evening Standard: "We are very thankful to this man for his swift intervention that helped the officers detain the suspect.
"The video was brought to the attention of the Borough Commander who was very impressed and would like to meet the passer-by.
"So if you are reading this article please get in contact with me."
Scotland Yard said officers were patrolling near Clarence Street, Kingston, around 11.20pm on Saturday when they received a report that two males were selling drugs nearby.
The spokesperson said the males left before police arrived, but one of them was stopped near to the scene. He then attempted to flee the scene, before he was arrested.