South Korea has unveiled a group of cloned dogs which it is hoped will boost the detection of illegal drugs.

The Labrador retrievers were born about five months ago after being separately cloned from an experienced drug-sniffing canine in active service.

In February, all seven passed a major behaviour test aimed at finding whether they are genetically qualified to work as sniffing dogs.

Typically only 10 -15 per cent of dogs born naturally pass the test.

For now, the canines all share the same name - Toppy, which is a combination of the words "tomorrow" and "puppy".

The Korean Customs Service said the clones will be used to help identify illegal drugs and explosives being smuggled in or out of the country.

Commissioner Hur Yong-suk, said: "Drug-sniffing dogs detect about 40 per cent of all narcotics being discovered, so if we just have an excellent drug-sniffing dog, we can increase this 40 per cent to 60 to 70 per cent in the future."

The cloning work was conducted by a team of Seoul National University scientists who in 2005 successfully created the world's first known dog clone, an Afghan hound named Snuppy.

If the cloned dogs succeed in other tests for physical strength, concentration and sniffing ability, they will be put to work by July next year at airports and harbours across South Korea.

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