During the Korean War (1950–1953), China and North Korea accused the US of waging bacteriological warfare, including the use of biological weapons developed Japanese war criminals from Unit 731, who had been convicted during the Khabarovsk Trials in 1949. The Soviet Union did not immediately join in the allegation campaign against the Allies, with the Soviet Foreign Ministry initially taking a restrained stance. However, with Moscow’s backing and active involvement in international orga nisations and the media, a powerful propaganda campaign was unleashed against American-led UN troops in Korea, as well as the political leadership of the US. The campaign was markedly political in nature and it involved many prominent individuals, including public figures from Western countries. An extensive action plan was developed, although its implementation was incoherent, which was a reflection of both the lack of evidence and a rapidly changing international environment.