This laboratory was built in 1941, when part of China was occupied by Japan for several years, and worked until the end of the Second World War. Its exact location was not yet known. Unit 731 began operations as a Japanese medical unit in 1931, but quickly expanded its research to include brutal biological and chemical warfare experiments using Chinese, Korean, Russian, and American POWs as test subjects.

shelter of fear

Researchers from the Heilongjiang Provincial Institute of Cultural Relics and Archaeology, who excavated the bunker, said the discovery “highlights the legacy of Unit 731’s brutality and its impact on global efforts to prevent biological warfare.”

• About 12,000 men, women and children were killed as a result of Unit 731’s sadistic experiments involving grenades, bacterial bombs, flamethrowers and chemical weapons.
• People were also dehydrated, killed in centrifuges, injected with animal blood, exposed to X-rays, cut open without anesthesia, and kept in low-pressure chambers until their eyes popped.
• Plague-infected fleas grown in Unit 731 laboratories were also dropped by planes over Chinese cities, causing disease outbreaks that killed hundreds of thousands of people.

Archaeologists have partially excavated a U-shaped structure about 33 meters long and 21 meters wide, through which interconnected rooms and tunnels lie. The exact purpose of each room has yet to be determined, as archaeologists have yet to dig inside, but researchers have classified what they believe to be laboratories, observation and examination rooms, prison cells, barracks, garages, bathhouses, dining rooms, and wells.

As Live Science points out, after Japan’s surrender in September 1945, the United States hid evidence of the horrific experiments and secretly granted immunity from prosecution for war crimes to many Unit 731 leaders in exchange for their investigations. Much of this information was then transferred to Fort Detrick in Maryland, which was the headquarters of the US Cold War biological weapons program from 1943 to 1969.