Bones unearthed from a wartime Army Medical School site in Tokyo decades ago, potentially linked to victims of Japan’s notorious Unit 731, remain in a repository awaiting identification.
Activists, historians, and experts marked the 35 anniversary of the discovery, renewing calls for an independent investigation into the bones’ connection to human germ warfare experiments.
Unit 731, headquartered in then-Japanese-controlled northeast China, was responsible for injecting prisoners of war with typhus, cholera, and other diseases, performing unnecessary amputations and organ removals, and freezing prisoners to death in endurance tests. Japan’s government has acknowledged only that Unit 731 existed.
In 1989, around a dozen skulls, many with cuts, and parts of other skeletons were unearthed during construction at the site of the wartime Army Medical School. The school’s ties to a germ and biological warfare unit led many to suspect a dark history.
A previous Health Ministry investigation in 2001 concluded that the remains were most likely from bodies used in medical education or brought back from war zones, based on interviews with 290 people associated with the school. However, some interviewees suggested connections to Unit 731, mentioning specimens from the unit being stored at the school.
A 1992 anthropological analysis found that the bones came from at least 62 and possibly more than 100 different bodies, mostly adults from parts of Asia outside Japan. The holes and cuts found on some skulls were made after death, it said, but did not find evidence linking the bones to Unit 731.
Activists argue the government could do more to uncover the truth, including publishing full accounts of its interviews and conducting DNA testing.
Kazuyuki Kawamura, a former Shinjuku district assembly member, recently obtained 400 pages of research materials from the 2001 report using freedom of information requests. He claims the government “tactfully excluded” key information from witness accounts.
The newly published material includes vivid descriptions from witnesses, such as one who described seeing a head in a barrel and helping to handle it before running off to vomit. These accounts suggest that more forensic investigation might show a link to Unit 731.
“Our goal is to identify the bones and send them back to their families,” said Kawamura. “We just want to find the truth”, according to AP.
Health Ministry official Atsushi Akiyama said witness accounts had already been analysed and factored into the 2001 report, and the government’s position remains unchanged. He noted that a lack of documentary evidence, such as labels on specimen containers or official records, is a key missing link.
Documents involving Japan’s wartime atrocities were carefully destroyed in the war’s closing days, making new evidence difficult to find. Akiyama added that the lack of information about the bones would make DNA analysis challenging.
Hideo Shimizu, who was sent to Unit 731 in April 1945 at age 14 as a lab technician, recalls seeing heads and body parts in formalin jars stored in a specimen room. He was told they were “maruta” — logs — a term used for prisoners chosen for experiments.
Days before Japan’s 15 August 1945 surrender, Shimizu was ordered to collect bones of prisoners’ bodies burned in a pit. He was then given a pistol and cyanide to kill himself if caught on his journey back to Japan.
Shimizu said he cannot tell if any specimen he saw at Unit 731 could be among the Shinjuku bones but emphasised that what he witnessed in Harbin should never be repeated. “I want younger people to understand the tragedy of war,” he said.
Activists, historians, and experts marked the 35 anniversary of the discovery, renewing calls for an independent investigation into the bones’ connection to human germ warfare experiments.
Unit 731, headquartered in then-Japanese-controlled northeast China, was responsible for injecting prisoners of war with typhus, cholera, and other diseases, performing unnecessary amputations and organ removals, and freezing prisoners to death in endurance tests. Japan’s government has acknowledged only that Unit 731 existed.
In 1989, around a dozen skulls, many with cuts, and parts of other skeletons were unearthed during construction at the site of the wartime Army Medical School. The school’s ties to a germ and biological warfare unit led many to suspect a dark history.
A previous Health Ministry investigation in 2001 concluded that the remains were most likely from bodies used in medical education or brought back from war zones, based on interviews with 290 people associated with the school. However, some interviewees suggested connections to Unit 731, mentioning specimens from the unit being stored at the school.
A 1992 anthropological analysis found that the bones came from at least 62 and possibly more than 100 different bodies, mostly adults from parts of Asia outside Japan. The holes and cuts found on some skulls were made after death, it said, but did not find evidence linking the bones to Unit 731.
Activists argue the government could do more to uncover the truth, including publishing full accounts of its interviews and conducting DNA testing.
Kazuyuki Kawamura, a former Shinjuku district assembly member, recently obtained 400 pages of research materials from the 2001 report using freedom of information requests. He claims the government “tactfully excluded” key information from witness accounts.
The newly published material includes vivid descriptions from witnesses, such as one who described seeing a head in a barrel and helping to handle it before running off to vomit. These accounts suggest that more forensic investigation might show a link to Unit 731.
“Our goal is to identify the bones and send them back to their families,” said Kawamura. “We just want to find the truth”, according to AP.
Health Ministry official Atsushi Akiyama said witness accounts had already been analysed and factored into the 2001 report, and the government’s position remains unchanged. He noted that a lack of documentary evidence, such as labels on specimen containers or official records, is a key missing link.
Documents involving Japan’s wartime atrocities were carefully destroyed in the war’s closing days, making new evidence difficult to find. Akiyama added that the lack of information about the bones would make DNA analysis challenging.
Hideo Shimizu, who was sent to Unit 731 in April 1945 at age 14 as a lab technician, recalls seeing heads and body parts in formalin jars stored in a specimen room. He was told they were “maruta” — logs — a term used for prisoners chosen for experiments.
Days before Japan’s 15 August 1945 surrender, Shimizu was ordered to collect bones of prisoners’ bodies burned in a pit. He was then given a pistol and cyanide to kill himself if caught on his journey back to Japan.
Shimizu said he cannot tell if any specimen he saw at Unit 731 could be among the Shinjuku bones but emphasised that what he witnessed in Harbin should never be repeated. “I want younger people to understand the tragedy of war,” he said.