Four men have been arrested after police found a handgun and knives in their vehicle in Uxbridge town centre.
A large number of police cars were sent to Uxbridge High Street on Tuesday (July 18) at around 6pm.
A Met Police spokesman said: "Three males located in a vehicle. In the vehicle was a handgun and a number of knives. Fourth male located in an address.
"Four males all aged 19 currently in custody in a west London police station.
Twitter user @DavidAkinsanya posted a photograph showing a number of police cars near Rush Fitness gym in the town centre.
Other people reported seeing a helicopter and a large police presence.
Police confirmed the three men found in the car were arrested on suspicion of possession of an offensive weapon and possession of a firearm.
The fourth man, arrested at an address nearby the High Street gym, was arrested on the same charges.
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