POLICE in Winchester have renewed their appeal for witnesses following the theft of a £30,000 diamond ring from a city jewellers.

New analysis of CCTV footage has shown up to three men may have been involved in the incident.

Police in the city had been searching for just two men in connection with the heist, after the ring was grabbed from jewellers Jeremy France last Tuesday.

Shortly after 3.10pm a man entered the shop and approached the 18-year-old shop assistant asking to see two diamond-encrusted rings on display in the shop's window.

The assistant, feeling out of her depth, asked the man to wait while she called for manager Jeremy France. However, as he approached, the man grabbed the more expensive of the two pieces and ran off.

The ring, pictured above, a white diamond solitaire, is not only unique but the biggest ring the jewellers have ever stocked with a 2.34 carat main stone surrounded by two others and set in platinum.

However, detectives now say the CCTV footage shows three men loitering under a covered pedestrian walkway in Tower Street just minutes before the raid took place.

The first man wore a light-coloured shirt and jeans. The second wore a grey shirt or top, and the third was in a blue checked shirt.

The third man is the one who snatched the ring from the shop and was then chased by Mr France along Upper High Street before losing him at the corner of Tower Street.The thief is described as a 25-year-old white man of proportionate build who is 5ft 10in with short brown hair. He is missing an upper right front tooth and was wearing a long-sleeved blue check shirt, dark blue jeans and trainers.

The thief then jumped into a white Ford Mondeo, which sped out of Tower Street past Winchester train station to Sussex Street and continued on to Andover Road North, heading towards the A34.

Anyone with any information is asked to contact DC Gary Steward on 0845 045 4545, or the anonymous Crimestoppers line on 0800 555 111.