1933-1945
A society for the history of the Pacific war in Tokyo's private Keio University discovers "highly confidential" documents of Japan's Unit 731 in a used bookstore in August 1984. The documents describe microbial experiments conducted on Chinese prisoners of war (POW). According to the documents, more than 3,000 persons, mostly Chinese, were used for live experiments at a center in Harbin in northeast China during World War II. POWs were shot with bacterial shells, including tetanus bacilli, to measure muscle changes.
--"Reports Found in Tokyo Reveal War Crimes in China," Xinhua News Agency, 15 August 1984; "Documents on Germ-Poison Tests on POW's Discovered," Kyodo News Service, 15 August 1984; in Lexis-Nexis, http://web.lexis-nexis.com.

1937-1945
According to a Kyodo News Service report, the Japanese Imperial Army sprays germ-contaminated fleas over Zhejiang Province in Central China.
--"400 Chinese Killed in Germ Warfare in China-Japan War," Japan Economic Newswire/Kyodo News Service, 10 January 1993; in Lexis-Nexis, http://web.lexis-nexis.com.

1937-1945
World War II era documents of the Japanese Army's general staff and medical officers show that the army plans to target several areas of the Asia-Pacific region with biological bombs, according to a report by Kyodo News Service. Target cities are located in Australia, India, Samoa, Burma, New Guinea, Hawaii, Guam, and Saipan.
--"Former Japanese Army Targeted Pacific for Germ Bombs," Kyodo News Service, 28 November 1993; in Lexis-Nexis, http://web.lexis-nexis.com.

August 1938
Japan's Unit 731 sprays cholera germs in Beijing killing more than 300 people.
--"Research Published on Japanese Bacteriological Warfare," BBC Summary of World Broadcasts, Part 3 Asia-Pacific, China, Foreign Relations, 16 August 1995; in Lexis-Nexis, http://web.lexis-nexis.com.

1939
Between 3,000 and 20,000 refugees from Guangdong and Hong Kong are killed in a series of bacteriological experiments at a Japanese military laboratory called Bo 8609. The estimates are based on research by historians at the Guangdong Academy of Social Science. Until 1994, it was believed that victims in Canton [Guangzhou] died from starvation and sickness.
--"Germ Warfare Lab Found in South China," United Press International, 23 November 1994; Kevin Rafferty, "'Up to 20,000 Died' in Japanese Germ Warfare Laboratory," The Guardian (London), Foreign, p. 18, 24 November 1994; in Lexis-Nexis, http://web.lexis-nexis.com.

1940
The Japanese army spreads plague-infected fleas from an airplane over Hangzhou.
--Mari Yamaguchi, "Japanese Biological Warfare Veteran Says He Cut Human 'Logs,'" Associated Press, 15 November 2000; in Lexis-Nexis, http://web.lexis-nexis.com.

27 October 1940
According to a Kyodo News Service report, a Japanese warplane sprays plague germ-infected wheat and corn over the city of Ningbo.
--"400 Chinese Killed in Germ Warfare in China-Japan War," Japan Economic Newswire/Kyodo News Service, 10 January 1993; in Lexis-Nexis, http://web.lexis-nexis.com.

1941
The Japanese army spreads plague-infected fleas from an airplane over Nanjing.
--Mari Yamaguchi, "Japanese Biological Warfare Veteran Says He Cut Human 'Logs,'" Associated Press, 15 November 2000; in Lexis-Nexis, http://web.lexis-nexis.com.

1950s
China conducts research on biological products such as vaccines as a precautionary measure against bacteriological warfare, as well as to wipe out epidemic diseases.
--"Biological Products Playing Important Role," Xinhua News Agency, 14 January 1991; in Lexis-Nexis, http://web.lexis-nexis.com.

1951-1953
Dozens of American prisoners of war (POW) captured during the Korean War reportedly may have been used for biological and medical experiments in a secret Chinese facility in Northeastern China. According to later reports, POWs are subjected to torture and tests using germ warfare. Sources for the report include a Defense Department investigation, an East European military source as well as the Defense Intelligence Agency.
Note: U.S. officials visiting Beijing in May 1992 question Chinese officials about the report, but China does not confirm the existence of the facility.
--"American POWs May Have Been Subjected to Experiments in China: Report," Agence France Presse, 3 July 1992; in Lexis-Nexis, http://web.lexis-nexis.com; Melissa Healey, "MIAs May Have Been Used as Test Subjects in China Servicemen: A U.S. delegation went to Beijing in May to inquire into the fate of Korean War soldiers," Los Angeles Times, Part A, Foreign Desk, p. 1, 3 July 1992.

13 July 1952
China accedes to the Geneva Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous, or Other Gases and of Bacteriological Methods of Warfare. Beijing declares it will abide by it as long as other signatories do the same. The Geneva Protocol was opened for signature on 17 June 1925 and entered into force on 8 February 1928.
--"Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare," Bureau of Public Affairs, U.S. Department of State, 25 September 2002. http://www.state.gov/t/ac/trt/4784.htm.

	Updated November 2005