An elderly man has been left in a critical condition after being knocked down by a gang riding mopeds.
The victim, in his early 80s, was hit by one of the six mopeds at around 8.30pm on January 3, as he crossed a road in the Kensal Rise area of north-west London.
The riders, wearing crash helmets, rode around him while he lay injured on the ground on Harrow Road, before "callously" driving off towards Wrottesley Road.
The man's family have been informed and officers from the Metropolitan Police's Serious Collision Investigation Unit are looking into the incident.
Police are appealing for any witnesses to come forward, or anyone with dash cam footage that may have recorded the moped riders.
Detective Constable Leo Christian said: "We are looking for any witnesses who saw the collision or the group of mopeds being ridden around the area.
"They callously rode off leaving an elderly man seriously injured in the road and did not even try to get him any help.
"We are determined to find those responsible and I would appeal to anyone who was part of this group of riders to do the right thing and come forward."
Any witnesses or anyone with any information is asked to call police on 020 8246 9820 or make contact via Twitter @MetCC. Please quote CAD 6673/03JAN.
To give information anonymously contact Crimestoppers on 0800 555 111.
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