Archaeologists have discovered an underground bunker in northeast China where Japanese scientists performed horrific biological experiments on human subjects during World War II, including subjecting their victims to dehydration, frostbite, and anthrax bombs.
The New York Post reported on Thursday that the derelict bunker was unearthed near the city of Anda in Heilongjiang province. Although the facility had been known about for nearly eight decades, its existence and precise location wasn't confirmed until a week ago, according to the South China Morning Post.
A partially U-shaped structure that measures roughly 108 feet long by 67 feet wide, the covert "horror bunker" was comprised of interconnected rooms and tunnels, including what archaeologists believed to be laboratories, observation and dissection rooms, and holding cells for human test subjects.
The Post reported that the underground site had been outfitted with defense mechanisms. The test field was ringed by barbed wire, while all laboratories, dissection bunkers, barracks, and other facilities were built below ground to maintain secrecy and to protect against air raids.
Unit 731, a branch of the Japanese Imperial Army during Japan's occupation of China from 1931 to 1945, ran the facility. The unit is widely considered to be responsible for performing heinous biological and chemical warfare experiments on Chinese, Korean, Russian, and American POWs, from 1935 until Japan's surrender in 1945.
Researchers from the Heilongjiang Provincial Institute of Cultural Relics and Archaeology said that the testing site near Anda "highlights the ongoing legacy of Unit 731's atrocities and their impact on global efforts to prevent biological warfare."
Live Science reported on Tuesday that up to 12,000 men, women, and children perished at the hands of Unit 731's scientists and their experiments, which included the testing of grenades, bacterial bombs, flamethrowers, and chemical weapons.
Victims were also spun to death inside centrifuges, lethally bombarded with X-rays, injected with animal blood, subjected to dehydration, vivisected without anesthesia, and imprisoned within low-pressure chambers until their eyeballs exploded.
Unit 731 was also responsible for breeding, then dropping plague-infected fleas over Chinese cities via low-flying planes. The unit's actions sparked disease epidemics that killed hundreds of thousands of people.
During his testimony to the Shenyang special military tribunal in 1956, Sakai Hayao, former commander of Unit 731's Lin Kou branch, recalled an "especially brutal" experiment conducted at Anda field. The test, designed to evaluate the effectiveness of weaponized microbes, involved tying individuals to wooden poles and strafing them with anthrax bombs.
Shortly before Japan's surrender in 1945, Unit 731 destroyed the facility to conceal all evidence of its experiments. According to the South China Morning Post, declassified documents revealed that the unit leaders involved with these atrocities shared data with U.S. authorities in exchange for immunity from being charged with war crimes.
The data was transferred to Fort Detrick, a U.S. Army research center in Maryland that developed biological weapons during the Cold War.
The Heilongjiang Provincial Institute of Cultural Relics and Archaeology's researchers hope that the discovery of the underground bunker will help bring to light the atrocities performed there. They intend to carry out further excavations in the area, so that they can generate a more accurate blueprint of the facility's layout.
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