GANGS of Eastern European criminals are making more money from illegally fishing for Scottish shellfish than from pushing drugs, it has been claimed.

Divers working for organised crime gangs are electrifying the seabed off the coast of Argyll and making up to £65,000 a day selling the illegally harvested razor clams on the black market.

Police have warned the ­criminals that they are putting their lives in danger by using the potentially lethal technique of using electricity in the sea.

Detective Chief Inspector Calum Young of Police Scotland's L Division - which covers Argyll, Bute and West Dunbartonshire - said: "They have a generator on the boat and deploy electrodes and probes on to the seabed and run them along the seabed, 10 to 15 metres deep.

"The electricity stuns the razor clams and divers walk behind the boat scooping the clams up.

"Many of the divers are known to be of eastern European origin and there is concern that they are being exploited and their personal safety is in danger - because of the proximity of electricity in water.

"There is a major concern that we will be faced with fatalities."

It is estimated that illegally active fishing boats are taking 500-600kg of razor clams a day, which are shipped away within 24 hours, having somehow obtained legal paperwork along the way, from Glasgow airport to Asian markets via Singapore.

A legal boat might recover only one or two kilos a day.

DCI Young added: "The money to organised crime and criminals is significant. It makes more than drugs does.

"When these skippers are approached, they throw any evidence of electro-fishing over the side of the boat."

It has been illegal since 1998 to use electro-fishing methods, but earlier this year the Scottish Government brought in tougher licensing measures.

Police Scotland confirmed one boat had been stopped last week under suspicion of being involved in electro-fishing.

Inquiries into the ownership of the boat by Marine Scotland are understood to be ongoing.

A multi-agency operation run from Oban, involving Police Scotland, Marine Scotland, Argyll and Bute Council and the Health and Safety Executive, has been launched to clamp down on ­electro-fishing for razor clams off the coast.

Shellfish farmed in unclassified areas are deemed unfit for human consumption and cannot enter the food chain. People who eat illegally harvested products may suffer nausea, blindness and in severe cases respiratory paralysis or death.

Earlier this year a consignment of illegally harvested razor clams was seized amid fears it could cause food poisoning. The 815kg catch from waters around Barra, worth about £40,000, was destroyed after being intercepted in Argyll en route to Hong Kong.

The former British colony's government had previously warned about the import of certain razor clams from Scotland that were considered potentially poisonous.

Last month new measures were introduced to tackle the illegal fishing method. New licensing means vessels will be inspected by Marine Scotland officers to ensure equipment capable of ­electro-fishing is not installed.

At the launch, Environment ­Secretary Richard Lochhead said: "Electro-fishing for razor clams remains illegal and may endanger those working in the industry as well as stocks of razor clams and the wider environment.

"We need strong scientific evidence on the impact of electrofishing on the wider marine environment before we will consider supporting any bid to relax European laws that prohibit it."