Four people have been arrested after detectives foiled a smash and grab robbery at a luxury jewellers in Mayfair.

The men arrived on mopeds outside the Parmigiani store in Mount Street and started breaking the glass of the jewellery store using hammers.

But before they could enter the premises undercover officers arrived in a black taxi and stopped the robbery.

Two men both aged, 18, and a 16-year-old man are currently being held at central London police stations.

Another 17-year-old has been taken to hospital with a minor hand injury.

A witness said: "There were dozens of police everywhere very quickly. One of the robbers was sitting on the floor looking dazed and he was being treated for a cut to his hand."

Detective chief inspector Paul Johnson said: "This morning's arrests are another successful operation by the Met's Flying Squad who are committed to tackling smash and grab robberies. This type of offence is not a victimless crime and we will continue to pursue relentlessly those who persist in committing robbery.

"I hope that this morning's operation and recent arrests and convictions the Flying Squad have secured send a strong message of deterrent to would-be-robbers, that they will be identified and brought to justice."

It comes within weeks of a separate jewellery raid at the Dorchester Hotel. Reed Roberts, 23, and Skye Roberts, 19, both of Cubitt Street, were remanded in custody after being charged with the hotel's robbery.