Bird flu outbreak in North Korea

Hundreds of thousands of chickens are said to have been culled

North Korea says it has had a first outbreak of the deadly bird flu virus.

The state Korean Central News Agency said no people had been infected but hundreds of thousands of chickens had been culled and the carcasses burned.

The agency only said that the outbreak was "recent" and occurred at "two or three" chicken farms. It did not specify the virus type.

The H5N1 virus has killed almost 50 people since its resurgence in South East Asia in December 2003.

Tight controls

KCNA said Hadang farm in Pyongyang, among the city's largest, was one of the sites of the outbreak.

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North Korea had previously said it was free of the virus that has struck many countries in south and east Asia.

South Korean news agency Yonhap earlier this month reported an outbreak at Hadang, prompting the World Health Organization (WHO) to ask the reclusive North for information.

The North has relied on food aid for more than a decade but imposes tight controls on foreign visitors and aid workers.

Experts fear the H5N1 virus could eventually combine with human flu and threaten a deadly pandemic.

There are suspected cases of the virus being passed between humans.

So far, Vietnam has been the country hardest hit by this outbreak of bird flu.