'Grave' bird flu threat to China

China's latest outbreak is of the deadly H5N1 strain

China faces a "grave" threat from bird flu, Vice-Premier Hui Liangyu has warned.

China said it was intensifying its battle against the virus, by introducing more rigorous monitoring and immunisation of birds.

"We cannot let down our guard, we cannot underestimate the risks of the outbreaks," Mr Hui said.

The ministry of agriculture revealed that more than 91,000 birds had been culled following a new outbreak.

On Wednesday China said 2,600 birds had been found to have died from the disease in Inner Mongolia.

The deaths, at a farm near the region's capital of Hohhot, were due to the H5N1 strain, which is potentially lethal to humans, the Xinhua news agency said.

Joint measures

A local official told the AFP news agency that the latest outbreak had been detected at a small farm with fewer than 10,000 birds, mainly chickens, geese and peacocks.

H5N1 BIRD FLU VIRUS Principally an avian disease, first seen in humans in Hong Kong, 1997 Almost all human cases thought to be contracted from birds Isolated cases of human-to-human transmission in Hong Kong and Vietnam, but none confirmed Q&A: Avian flu

In Thailand a villager has become the 13th person in the country to die from bird flu, but the first this year, while the man's son is being treated for flu-like symptoms, the Thai prime minister said.

Bird flu has killed at least 60 people in Asia since December 2003.

It has also now spread to Europe, with cases confirmed in Romania, Turkey and Russia, and suspected in the Former Yugoslav Republic of Macedonia and Greece.

On Thursday European health ministers met in the UK to discuss how to implement a joint response to bird flu on the continent.

The UN's Food and Agriculture Agency has also warned of a risk the disease will now reach the Middle East and Africa as a result of the European outbreaks.

Scientists fear the H5N1 strain could combine with human flu or mutate into a form that it easily transmissible between humans, triggering a flu pandemic.