US officials had claimed that 1949 Soviet war crimes trial of Japanese officers was propaganda ploy. Of course, US was in process of developing extensive chemical and biological warfare capability with help of Japanese officers that *it* had captured and protected from war crimes prosecution in exchange for their assistance in germ warfare efforts.
Stephen Endicott has been studying US use of biological warfare in Korea in early 1950s for long time. I recall reading article by him about this matter in now-long defunct journal called *Modern China* in late 1970s. Michael Hoover