A Japanese expert has found a series of documents about the Japanese aggressive army's Unit 731 that carried out the brutal germ warfare in China during World War II, causing deaths of many Chinese people, the Tokyo News reported Wednesday.

The two declassified documents were found in the US National Archives by Keiichi Tsuneishi, professor at Kanagawa University and an expert on biological and chemical weapons, the newspaper said.

One of the top-secret documents was a report on bacteriological warfare for the chief of staff of the Far Eastern Commission, dated July 17, 1947, compiled by Brig. Gen. Charles Willoughby, head of the "G2" intelligence unit of the US-led postwar occupation forces in Japan.

The other was a letter dated July 22 the same year that Willoughby sent to Maj. Gen. S. J. Chamberlin, director of intelligence of the US War Department General Staff, to illustrate the need for continued use of confidential funds without restrictions to obtain such intelligence.

In the documents, Willoughby described the achievements of his unit's investigations, saying the "information procured will have the greatest value in future development of the US BW (bacteriological warfare) program."

Citing a US War Department specialist in charge of the investigation, Willoughby wrote in the report that "data on human experiments may prove invaluable" and said the information was "only obtainable through the skillful, psychological approach to top-flight pathologists" involved in Unit 731 experiments.

According to Tokyo News, besides the two documents from US archives, Tsuneishi also found a secret book in Japan's national congressional library -- Reports of Epidemic Prevention Development for Medical Academy of Land Forces.

The reports in the book reveal that Unit 731, established by the Imperial Japanese Army in 1936, developed many biological weapons using plague, anthrax and other bacteria, and conducted related human experiments during the war, the daily said.

Headquartered in the suburbs of Harbin in northeast China's Heilongjiang Province, the unit conducted germ warfare in various places in China and used Chinese as subjects in human experiments, resulting in deaths and injuries of tens of thousands of people.

The documents also indicated that the biological weapons of Unit 731 originally targeted the Soviet Union, the newspaper noted.

(Xinhua News Agency August 18, 2005)