Unit 731 (731 部隊, Nana-san-ichi butai?) was a covert biological and chemical warfare research and development unit of the Imperial Japanese Army that undertook lethal human experimentation during the Second Sino-Japanese War (1937–1945) and World War II. It was responsible for some of the most notorious war crimes carried out by Japanese personnel.
Unit 731 was the code name (tsūshōgō) of an Imperial Japanese Army unit officially known as the Kempeitai Political Department and Epidemic Prevention Research Laboratory. It was initially set up under the Kempeitai military police of the Empire of Japan to develop weapons of mass destruction for potential use against Chinese, and possibly Soviet forces.
Unit 731 was based in the Pingfang district of Harbin, the largest city in the Japanese puppet state of Manchukuo (now Northeast China).
More than ten thousand people, from which around 600 every year were provided by the Kempeitai, were subjects of the experimentation conducted by Unit 731.
More than 95 percent of the victims who died in the camp based in Pingfang were Chinese and Korean, including both civilian and military. The remaining 5 percent 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.
According to the 2002 International Symposium on the Crimes of Bacteriological Warfare, the number of people killed by the Imperial Japanese Army germ warfare and human experiments is around 580,000. According to other sources, the use of biological weapons researched in Unit 731's bioweapons and chemical weapons programs resulted in possibly as many as 200,000 deaths of military personnel and civilians in China
Many of the scientists involved in Unit 731 went on to prominent careers in post-war politics, academia, business, and medicine. Some were arrested by Soviet forces and tried at the Khabarovsk War Crime Trials; others surrendered to the American Forces.
On 6 May 1947, Douglas MacArthur, as Supreme Commander of the Allied Forces, wrote to Washington that "additional data, possibly some statements from Ishii probably can be obtained by informing Japanese involved that information will be retained in intelligence channels and will not be employed as 'War Crimes' evidence." The deal was concluded in 1948.
Because of their brutality, Unit 731's actions have since been declared by the United Nations to have been crimes against humanity.
Vivisection
-Prisoners of war were subjected to vivisection without anesthesia.
-Vivisections were performed on prisoners after infecting them with various diseases.
-Scientists performed invasive surgery on prisoners, removing organs to study the effects of disease on the human body. These were conducted while the patients were alive because it was feared that the decomposition process would affect the results.The infected and vivisected prisoners included men, women, children, and infants.
-Vivisections were also performed on pregnant women, sometimes impregnated by doctors, and the fetus removed.
-Prisoners had limbs amputated in order to study blood loss.
Those limbs that were removed were sometimes re-attached to the opposite sides of the body.
-Some prisoners' limbs were frozen and amputated, while others had limbs frozen then thawed to study the effects of the resultant untreated gangrene and rotting.
-Some prisoners had their stomachs surgically removed and the esophagus reattached to the intestines.
-Parts of the brain, lungs, liver, etc. were removed from some prisoners
Weapons testing
-Human targets were 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.
Germ warfare attacks
-Prisoners were injected with inoculations of disease, disguised as vaccinations, to study their effects.
-To study the effects of untreated venereal diseases, male and female prisoners were deliberately infected with syphilis and gonorrhea, then studied.
-Prisoners were infested with fleas in order to acquire large quantities of disease-carrying fleas for the purposes of studying the viability of germ warfare
-Plague fleas, infected clothing, and infected supplies encased in bombs were dropped on various targets. The resulting cholera, anthrax, and plague were estimated to have killed around 400,000 Chinese civilians.
-Tularemia was tested on Chinese civilians.
-Unit 731 and its affiliated units (Unit 1644, Unit 100, et cetera) were actively involved not only in research and development, but also in experimental deployment of epidemic-creating biowarfare weapons in assaults against the Chinese populace (both civilian and military) throughout World War II. Plague-infested fleas, bred in the laboratories of Unit 731 and Unit 1644, were spread by low-flying airplanes upon Chinese cities, coastal Ningbo in 1940, and Changde, Hunan Province, in 1941. This military aerial spraying killed thousands of people with bubonic plague epidemics.
Biological warfare
Japanese scientists performed tests on prisoners with plague, cholera, smallpox, botulism and other diseases. This research led to the development of the defoliation bacilli bomb and the flea bomb used to spread the bubonic plague. Some of these bombs were designed with ceramic (porcelain) shells, an idea proposed by Ishii in 1938.
These bombs enabled Japanese soldiers to launch biological attacks, infecting agriculture, reservoirs, wells, and other areas with anthrax, plague-carrier fleas, typhoid, dysentery, cholera, and other deadly pathogens. During biological bomb experiments, scientists dressed in protective suits would examine the dying victims. Infected food supplies and clothing were dropped by airplane into areas of China not occupied by Japanese forces. In addition, poisoned food and candies were given out to unsuspecting victims and children, and the results examined.
Btw,
Hiroshima HQ
A top secret factory in Ōkunoshima produced chemical weapons for the Japanese military and medical units. Starting with mustard gas production in 1928, the factory moved on to such poisons as Lewisite, and Cyanogen. During the 1930s, as the war in China grew worse, the island the factory sat on was removed from most maps to strengthen secrecy and security.
After Imperial Japan surrendered to the Allies in 1945, Douglas MacArthur became the Supreme Commander of the Allied Powers, rebuilding Japan during the Allied occupation. MacArthur secretly granted immunity to the physicians of Unit 731 in exchange for providing America with their research on biological warfare
Some former members of Unit 731 became part of the Japanese medical establishment. Dr. Masaji Kitano led Japan's largest pharmaceutical company, the Green Cross. Others headed U.S.-backed medical schools or worked for the Japanese health ministry. Shiro Ishii in particular moved to Maryland to work on bio-weapons research.