AN Ipswich jewellery store owner today told of the moment a thief snatched an £8,000 platinum diamond ring before "running for his life" past lunchtime shoppers.

AN Ipswich jewellery store owner today told of the moment a thief snatched an £8,000 platinum diamond ring before "running for his life" past lunchtime shoppers.

Clare Andrews, owner of Andrews Jewellers in Ipswich's Thoroughfare, said staff were left stunned by the opportunist theft yesterday .

"It's very gutting. We've never had anything like this happen before," she said.

"We're all quite shaken."

The man, aged in his 30s, entered the store just after 12.10pm and asked to see the ring, which had been displayed in the shop's front window.

"He came in immediately behind another lady," Ms Andrews said.

"The colleague that was serving the lady asked if they were together and he said 'yes' and she said 'no'.

"He wanted to look at the £8,000 diamond ring we had in the window.

"He asked to look at it, my colleague got it out of the window and moments later he literally snatched it out of her hands."

Staff at the shop believe the thief viewed the same ring on Monday before returning yesterday to steal it.

"We believe the same gentleman and an accomplice came in here. They looked at the same ring," Ms Andrews said.

"I think they came to look at it and then came to finish the job.

"I think he planned it."

She added: "It's a beautiful, beautiful ring. It's very recognisable."

After snatching the ring from the assistant the man darted out of the store and ran toward the Cornhill.

A witness told staff that she had then seen him running in the direction of Queen Street or Princes Street.

"When he left he had a sheepskin hat with flaps. By the time the other witness saw him we believe he'd changed to a blue baseball cap," Ms Andrews said.

"He was running like his life depended on it."

The theft was caught on three closed circuit television cameras and the footage has been handed to Ipswich police.

They are appealing for anyone who saw the man at the time of the theft or as he ran through Ipswich town centre to contact them.

Police spokeswoman Lisa Miller said: "This was a particularly busy time of the day with people on their lunch breaks.

"Anyone who either witnessed this incident or saw a man matching this description should call Pc Belinda Stokes on 01473 613500 or Crimestoppers on 0800 555 111."

The thief is described as 5ft 8in and of medium build. At the time of the theft he was wearing a dark three-quarter length jacket, dark trousers, trainers and a dark brown sheepskin hat.