Local officials first reported the two outbreaks on Nov. 9, and the National Avian Flu Reference Laboratory confirmed on Monday that both had been caused by the deadly H5N1 flu strain.

Xinhua did not specify how many birds had died in the outbreak near Urumqi. Earlier a Hong Kong newspaper controlled by the mainland authorities, Ta Kung Pao, reported on its Web site that 1,400 chickens had been found dead there.

Experts from the agriculture department went to Xinjiang to investigate the two outbreaks, and 322,500 domestic poultry were culled around the two areas, Xinhua reported.

Battling to control several outbreaks of the H5N1 virus, China vowed on Tuesday to vaccinate its entire stock of 14 billion poultry, with the government footing the bill, as it scrambles to prevent more outbreaks.

Jia Youling, director-general of the Agriculture Ministry's veterinary bureau,, said Beijing would cover 50 to 80 percent of provinces' costs of vaccinating all their poultry, Xinhua said.

It gave no timetable for the inoculation campaign.

China has yet to report a confirmed human case but is probing a possible one in a northeastern province, the World Health Organisation said on Monday. It was the second area of the country to make such a precautionary diagnosis.

The virus has killed more than 60 people elsewhere in Asia since 2003. Almost all had been in close contact with infected birds.

Health experts fear millions could be killed around the world if the virus mutates to the point where it could spread easily from person to person.

The WHO is sending a team this week to the southern province of Hunan to investigate three other pneumonia cases which China said could not be ruled out as bird flu. The three lived close to the site of a poultry outbreak.

One of the pneumonia patients, a 12-year-old girl, died.

Tests to confirm or deny bird flu in the three would take at least a week, WHO said.