KHABAROVSK, Russia -- Late in December 1949, Soviet Communist Party leaders began distributing tickets in factories and institutes for an upcoming trial. Twelve Japanese physicians and military officers -- former researchers at a secret facility near Harbin, China known as Unit 731 -- stood accused of manufacturing biological and chemical weapons following experiments on human guinea pigs. And somewhere it was decided that the masses should hear firsthand what had gone on at the sprawling complex, which had been dynamited by the Japanese as Soviet troops advanced at the end of World War II.

The proceedings began in an orderly fashion, with the audience sitting quietly in the hall and balconies of the colonnaded Soviet Army Officers' House where the trial was held. But revelations about the alleged crimes soon shocked listeners. Graduates of Japan's leading medical universities, prosecutors said, had infected their victims with typhus, anthrax, cholera and bubonic plague -- and later loosed the diseases in Chinese villages. A three-day-old baby was said to have been jabbed with needles and submerged in icy water and live victims dissected without anesthesia. Circles of doctors would cut open screaming women to examine their reproductive organs.

"The first day, everything was quiet in town," said Georgy Permyakov, an 83-year-old language instructor who was the chief translator for the trial. "But there were two trial times a day, morning and evening, and when the spectators left the first morning session, they started calling and talking to each other. And after the evening session the entire city starting talking about it."