With the establishment of the puppet state of Manchukuo , the so-called " pacification of Manchukuo " began , as volunteer armies continued to fight the Japanese . Harbin became a major operations base for the infamous medical experimenters of Unit 731 , who killed people of all ages and ethnicities . All these units were known collectively as the '' Epidemic Prevention and Water Purification Department of the Kwantung Army '' . The main facility of the Unit 731 was built in 1935 at Pingfang District , approximately south of Harbin urban area at that time . Between 3,000 and 12,000 citizens including men , women , and children — from which around 600 every year were provided by the '' Kempeitai '' — died during the human experimentation conducted by Unit 731 at the camp based in Pingfang alone , which does not include victims from other medical experimentation sites . Almost 70 percent of the victims who died in the Pingfang camp were Chinese , including both civilian and military . Close to 30 percent of the victims were Russian . The Russian Fascist Party had the task of capturing " unreliable " Russians living in Harbin to hand over to Unit 731 to serve as the unwilling subjects of the gruesome experiments . Some others were South East Asians and Pacific Islanders , at the time colonies of the Empire of Japan , and a small number of the prisoners of war from the Allies of World War II ( although many more Allied POWs were victims of Unit 731 at other sites ) . Prisoners of war were subjected to vivisection without anesthesia , after infected with various diseases . Prisoners were injected with inoculations of disease , disguised as vaccinations , to study their effects . Unit 731 and its affiliated units ( Unit 1644 and Unit 100 among others ) were involved in research , development , and experimental deployment of epidemic-creating biowarfare weapons in assaults against the Chinese populace ( both civilian and military ) throughout World War II . Human targets were also used to test grenades positioned at various distances and in different positions . Flame throwers were tested on humans . Humans were tied to stakes and used as targets to test germ-releasing bombs , chemical weapons , and explosive bombs . Twelve Unit 731 members were found guilty in the Khabarovsk War Crime Trials but later repatriated ; others received secret immunity by the Supreme Commander of the Allied Powers Douglas MacArthur before the Tokyo War Crimes Tribunal in exchange for biological warfare work in the Cold War for the American Force
Unit 731
Unit 731
Harbin