CCTV footage which appears to show a group on four mopeds breaking the leg of a tourist in an attempt to steal his watch has been shared by police.
The shocking video shows the man crawling away from the eight suspects after a moped collides with his leg in Westminster.
Police say the incident happened on Sunday, April 30, at 3.10am in Park Lane.
The man appears to initially escape the suspects unharmed but is caught moments later.
Detective Constable Richard Kidd said: "This happened just after 3am, when a group of four or possibly more mopeds riding together would have been conspicuous.
"I want to hear from anyone who recalls seeing such a group, or who may have seen the mopeds being abandoned - or perhaps being stored in a lockup or similar location - in the early hours of Sunday, April 30.
"One of the mopeds would have sustained damage to its left side."
The victim, a man in his 30s, was treated for a broken leg and his alleged attackers left the scene empty-handed.
Anyone with information about the incident should call Westminster CID via 101. To remain anonymous call Crimestoppers on 0800 555 111.
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