Part of Oxford Street was closed down last night over fears of a gunman on the busy shopping street.
The central London road was blocked during the search at around 9.30pm on Saturday.
Disorder broke out among a large crowd of people who had gathered at the scene outside a sweet shop.
Social media reports of ‘looting’ were not officially confirmed but a number of people were arrested on suspicion of affray.
The area around the shop was cordoned off and a social media video showed a teenager being taken away in cuffs.
Another video posted after 11pm showed the store was still cordoned off and children’s bikes were left abandoned outside.
No one was found to be carrying a gun despite reports, according to the Metropolitan Police.
One woman who claimed to have witnessed the incident said on Twitter ‘it was chaos’.
Another posted: ‘I’ve never seen so many police gathered in one place.’
A spokesperson said: ‘Police called 21:30hrs to report of a man with a firearm in [Oxford Street, Westminster].
‘Specialist firearms officers deployed immediately & conducted extensive area search. No suspects located. No reports of any injuries.
‘A large crowd gathered at scene, resulting in some small outbreaks of disorder. A number of people were arrested on suspicion of affray & taken into custody.’
Officers stayed on the scene for a number of hours.
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