Statistics Of Japanese Democide: Estimates, Calculations, And Sources
"From the invasion of China in 1937 to the end of World War II, the Japanese military regime murdered near 3,000,000 to over 10,000,000 people, most probably almost 6,000,000 Chinese, Indonesians, Koreans, Filipinos, and Indochinese, among others, including Western prisoners of war. This democide was due to a morally bankrupt political and military strategy, military expediency and custom, and national culture (such as the view that those enemy soldiers who surrender while still able to resist were criminals)."
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Japan's Unit 731: