A chest of antique coins worth up to £300,000 was stolen by a gang in a sting on two auctioneers as they drove away from a exhibition centre.

Experts fear that the collection, which featured two gold coins of priceless historical value, could have been melted down. One of the coins can be dated back to 1826 and was worth up to £35,000.

The gang of about six men and two women targeted two men from Dix Noonan Webb, the auctioneer, in South Kensington, London, when the coins had been displayed at Earl’s Court Exhibition Centre. It is believed that the gang sabotaged the men’s car and followed them from the centre.

As the auctioneers drove away, they were approached by at least one member of the gang who told them that they had a flat tyre. The men stopped, pumped up the tyre up and continued on their way but soon realised it was flat again.

As they got out to have another look, a Mediterranean-looking man and other members of the gang approached and asked for directions. They pulled out a map for the auctioneers to look at, distracting them. The chest of coins was taken from the car by another member of the gang. Not realising what had happened, the two men finished changing the wheel and continued their journey.

When they arrived at their offices after the theft in September, they discovered that the chest of coins was missing. Details of the elaborate sting have only just been released by the police as they continue to hunt for the gang.

Detective Sergeant Neil Phillpot, from Notting Hill CID, said: “We believe this was an organised crime involving at least seven suspects. We are keen to trace them and believe they may be from Central or South America.”

Piers Noonan, of the auctioneers, said: “One five pound coin made in 1826 during the reign of George IV was worth £30,000 to £35,000 alone.

“We can trace its history from a Sotheby’s sale in 1854. It has always been rare and always been appreciated. It’s so rare it’s recognisable to collectors and almost unsellable in the public domain.

“The people who stole it got it for nothing and may just melt it down for a scrap dealer for about £500.” A mint condition £2 coin worth £15,000 to £18,000 and smelted in 1820 was also among the collection, which also included rare coins from Tibet, Austria, France, Australia and Burma.

Mr Noonan added: “It’s a huge loss. What we are talking about are several items which are unique and have been cherished for 200 years which could now be in a melting pot. It’s very disrespectful.

“Hopefully, this will be the biggest and only robbery in our history. We need to stop them doing it again as I believe the gang is still operating.”

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