A letter published by eight Chinese scientists in a June 22 issue of the New England Journal of Medicine said that the bird flu virus was isolated in a 24-year-old man who died in Beijing in 2003.

The man was of active service. He was hospitalized for lung infection in November 2003 and died later due to deterioration. At that time, the possibility of SARS was ruled out, but the cause of his death remained unknown.

The ministry has made contact with the eight scientists, said Mao Qun'an, spokesman of the ministry.

"In accordance with World Health Organization and China's diagnostic standards for human avian influenza, parallel laboratory tests are needed for further confirmation," Mao said.

The Chinese Center for Disease Control and Prevention is conducting the tests, and the ministry will keep the WHO updated, added Mao.

Mao said China will report to the WHO when the test results are out.