Allegations of biological warfare in the Korean War

Allegations that the United States military used biological weapons in the Korean War (1950–53) were raised by the governments of People's Republic of China, the Soviet Union and North Korea in 1952. The story was covered by the worldwide press and led to a highly publicized international investigation. US Secretary of State Dean Acheson and other US and allied government officials denounced the allegations as a hoax.

During 1951 the Communists made vague allegations of biological warfare, but these were not pursued. General Matthew Ridgway, United Nations Commander in Korea, denounced the initial charges as early as May 1951. He accused the communists of spreading "deliberate lies." A few days later, Vice Admiral Charles Turner Joy repeated the denials.

On 28 January 1952, the Chinese People's Volunteer Army headquarters received a report of a smallpox outbreak southeast of Incheon. From February to March 1952, more bulletins reported disease outbreaks in the area of Chorwon, Pyongyang, Kimhwa and even Manchuria. The Chinese soon became concerned when 13 Korean and 16 Chinese soldiers contracted cholera and the plague, while another 44 recently deceased were tested positive for meningitis. Although the Chinese and the North Koreans did not know exactly how the soldiers contracted the diseases, the suspicions soon shifted to the Americans.

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