The “free-range” eggs scam — under which eggs laid by battery hens in mainland Europe were sold as free-range or organic in British supermarkets — is ten times bigger than was first thought, it has emerged.

For up to five years consumers have been duped into paying premium prices for more than 500 million eggs, investigators have told The Times.

The scam, reported in The Times in November, has cost consumers £50 million. Tesco and Morrisons are among the supermarkets believed to have been victims.

The passing off of battery eggs as organic is a new part of the inquiry.

Enforcement officers now want to speak to a man caught by surveillance cameras trying to gain access to a safety deposit box in Kensington, West London. Investigators at the Department for the Environment, Food and Rural Affairs believe that he could provide a clue to the principals behind the fraud.

They wish to find whether a “broker”, based on the Continent, has set up an illicit egg supply to Britain.

What is known is that at least ten 44-tonne articulated lorries a week — each containing 224,000 eggs, the equivalent of 116 million a year — have been arriving in Britain from mainland Europe, probably for at least five years.

British authorities are now liaising with their EU counterparts to attempt to follow the trail back and to find out exactly who is behind the operation and how it has been executed.

The Times reported on November 16 last year that police had begun a criminal inquiry into the passing off of eggs from chickens reared in battery cages as free-range. This centred on a firm trading as Heart of England Eggs, a wholesale business based near Bromsgrove, Worcestershire.

Keith and Alan Owen, twin brothers, and Carol Owen, the wife of Keith, are on police bail while inquiries continue.

Five days after the revelations, the man who is in his late fifties or early sixties, turned up at the safety deposit centre and tried to access a storage facility being used as a postal address. The man said that he was acting on behalf of a relative.

However, he did not have the key or code to open the box, nor the necessary authorisation. When he was refused access he became angry and left empty-handed.

The box had been rented for cash in the name of Heinz Bernstein, who gave an address and telephone number in Herford, in North Rhine-Westphalia, Germany. The town is the home of the British Forces headquarters in Germany.

Investigators have attempted to track down Mr Bernstein but the person and address appear to be false. Officers believe that the man caught on film may be able to lead them to “Mr Bernstein”. They also suggest that the man may not be German and that people in Britain may recognise him.

Investigators are particularly intrigued because during separate inquiries into egg fraud three years ago a similar safety deposit centre in another part of Kensington was drawn to their attention.

This had been opened by a Hans Richter who gave an address within five miles of the address in Herford given by Mr Bernstein. This address also proved to be false. No CCTV images exist of Mr Richter.

There is no evidence so far of any unmarked eggs leaving Germany for Britain. Under EU egg marketing rules, all eggs must be stamped in the country where they are produced. In France, for example, they must be stamped FR. A code for the method of production is also obligatory. For battery caged eggs, this is number 3, for barn eggs 2, for free-range 1 and for organic 0.

Enforcement authorities believe the illicit trade has been made easier by a lack of inspection of eggs arriving at British ports. If any checks had been made, unstamped eggs would have been readily identified. The egg industry has already tightened its controls. The British Egg Industry Council says that it is determined to close all possible loopholes to protect consumers. It is particularly concerned because leading egg wholesalers and supermarkets were among the victims of the scam.

There is also concern because many factory-farmed eggs from EU countries contain high levels of salmonella.

The Food Standards Agency estimates that the bacteria are present in one in every 30 boxes of imported eggs on sale in Britain. There is a particular problem in Spain, where one in every eight boxes carries infected eggs.

Farmers in Britain are anxious to step up production of free-range eggs to meet a one million-a-week shortfall. They claim, however, that supermarkets should take some blame for this because they force prices down so low that they cannot afford to invest in new facilities. It costs between £300,000 and £500,000 to set up a free-range egg business.

Anyone with any information about the identity of the man caught on film is asked contact Defra Investigation Services on 0117 959-3111.

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