Police are renewing their appeal for witnesses after a gang kidnapped a jeweller at knifepoint and stole £80,000 worth of jewellery from his shop.

The ruthless raid took place on Boxing Day when the gang, who police are convinced are from Blackburn, kidnapped 31-year-old Pratim Soni near his shop in Preston.

The three masked kidnappers, who were possibly Asian, threatened to kill the businessman and harm his wife and children - and knew his exact address.

The victim used to be a jeweller in London but moved to Lancashire to escape the crime in the capital.

Detective Superintendent John Crichton, who is heading the investigation, said, "They were very determined criminals. There were times when the victim thought he might not have survived that night."

"The jewellery stolen was very common and we would urge any Asian jewellery shops to be on the look out for large amounts of gold and silver sold to them."

The ordeal started when the father-of-two left his shop, P and H Jewellers, in New Hall Lane, Preston at 6.15pm on Boxing Day.

As he stopped in his sea-blue BMW, registration number N208 NCK, at a nearby junction, two masked men jumped into his car, sitting in the passenger seat and in the back.

They jabbed a knife into his ribs, and possibly a gun, and made him drive around the block, where they were joined by a third kidnapper.

A mask was then put over the victim's head and he was tied up with wire and bundled into the boot of the car. They drove for about 15 minutes until they got to premises, possibly commercial. The victim said he could hear a shutter being used, children playing in the area and traffic.

The businessman was strapped into a chair with tape and again the kidnappers threatened to kill his family if he did not give them the keys and alarm code to his shop.

Fearing for his life he did what they said. The kidnappers then drove back to the shop and emptied it of an estimated £80,000 worth of Asian jewellery.

On their return they took the victim out of the premises and hid him in the back of a different, hatchback car.

They drove for 15 minutes and the victim was told to get out and face an alleyway wall until his kidnappers left. The alleyway, between Lambeth Street and Lincoln Road, runs parallel to Queen's Road, in Audley Range. He made his way to Fareed food takeaway, Audley Range. Shocked staff at the takeaway thought the man was joking when he wandered shakily into their business claiming to have been kidnapped.

Mr Crichton said, "They were prepared to use violence and made serious threats of violence towards his wife and family.

"They are extremely dangerous and determined. He was a very, very frightened man.

"During the course of taking statements from him he broke down a number of occasions."

The victim is now living away from his home address in Preston for fear of his family's safety.

The kidnappers were believed to be between 20 and 30 years old.

Anyone with any information should call the police on 01772 203203 or Crimestoppers on 0800 555 111.