A man was injured after an alleged knife fight broke out on the High Street in Uxbridge.
Armed police were called to the scene after a group of men were reported to be carrying knives, earlier this week.
The Metropolitan Police said they were called to reports of an altercation between a group of males on the High Street just after 4pm on Monday (April 3).
A Met Police spokesman said: "Some of the males were reported to be in possession of knives.
"Officers and firearms officers attended and one man was known to have received a minor injury.
"Police detained seven men and searched them.
"No knives or offensive weapons were found."
An 18-year-old man was arrested on suspicion of theft in relation to a credit card.
He was taken to a west London police station for questioning and he was further arrested on suspicion of breaching a criminal behaviour order.
He has been released under investigation and police enquiries continue.
Any witnesses or anyone with information can contact the police via 101 or @MetCC. To give information anonymously visit Crimestoppers or call on 0800 555 111.
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