This video shows the speedy response of police in Acton who were called to reports of an "imminent" street fight - but their blue lights and sirens caused a group of youths to disperse before they could even get started.
The footage, recorded by officers from Acton Central on Monday night (January 22), shows the view from behind the wheel as they raced to the scene.
They had left Ealing police station, in Uxbridge Road, and made their way to Bromyard Avenue, in the vehicle driven by Sergeant Matthew Buckland.
A spokesperson for Acton Central Police said: "We were responding to reports of 20 youths gathering around Bromyard Avenue.
"It was thought a fight was imminent, we responded with several other units."
The spokesperson added: "The arrival of the cars with lights and sirens from all directions had the desired effect.
"The group dispersed with no further hostility."
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