Mystery as bones found in Tokyo could be linked to Japan's horrifying human germ warfare experiments

Mystery surrounds skeletal remains unearthed at a Tokyo storehouse which experts believe could be linked to Japanese war crimes.

The bones that have sat for years in a Tokyo storehouse could either be remnants from early 20th century anatomy lessons, or they might belong to unidentified victims of one of Japan's most infamous war crimes. A group made up of activists, historians and other experts keen for the government to explore its links to wartime human germ warfare experiments gathered this weekend.

The collective marked the 35 years since their discovery and reiterated their call for an independent body to scrutinise the evidence. Japan's government has consistently side-stepped any discussion of wartime atrocities, including the sexual exploitation of Asian women known as "comfort women" and the forced labour of Koreans at Japanese mines and factories, often citing lack of documentary proof.

Despite apologies from Japan for their aggression in Asia, ever since the 2010s it has faced ongoing criticism from South Korea and China for regressing on these issues. Somewhere around a dozen skulls - many showing cuts, and pieces of others skeletons were uncovered on July 22, 1989 during the construction of a Health Ministry research centre, built on the site of the former Army Medical School.

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This School's strong connections to a unit specialising in germ and biological warfare, led many to suspect that these may be remains from a chapter of history the Japanese government has never officially acknowledged. Unit 731, based in the then-Japanese-controlled northeast China, is infamous for its brutal experiments on prisoners of war. Historians and former unit members reveal that these included injecting victims with typhus, cholera and other diseases.

The unit also performed unnecessary amputations and organ removals on living people to practice surgery and froze prisoners to death in endurance tests. However, Japan's government has only admitted to the existence of Unit 731. After the war, top officials from Unit 731 were not tried in postwar tribunals as the U. S. was keen to acquire chemical warfare data, according to historians.

Lower-ranked officials, however, faced trials by Soviet tribunals. Some of the unit's leaders went on to become medical professors and pharmaceutical executives after the war. A previous investigation by the Health Ministry concluded that the bones found could not be linked to the unit. The 2001 report suggested that the remains were most likely from bodies used in medical education or brought back from war zones for analysis.

This conclusion was based on questioning 290 people associated with the school. The report did acknowledge that some interviewees drew connections to Unit 731. One individual claimed to have seen a head in a barrel shipped from Manchuria, northern China, where the unit was based.

Two others mentioned hearing about specimens from the unit being stored in a school building, but had not actually seen them. Others denied the link, suggesting the specimens could include those from the prewar era.

A 1992 anthropological study revealed that the bones were from at least 62, possibly over 100 different bodies, primarily adults from regions of Asia outside Japan. The report stated that the holes and cuts found on some skulls were post-mortem, but it didn't find any evidence linking the bones to Unit 731.

However, campaigners argue that the government could do more to reveal the truth, such as publishing full accounts of its interviews and carrying out DNA tests. Kazuyuki Kawamura, a former Shinjuku district assembly member who has dedicated most of his career to solving the bone mystery, recently acquired 400 pages of research materials from the 2001 report through freedom of information requests. He claims it shows that the government "tactfully excluded" crucial information from witness accounts.

The newly released material doesn't provide definitive proof, but it does include graphic descriptions - one man recounted seeing a head in a barrel, handling it, and then running off to vomit - and comments from several witnesses who suggested that further forensic investigation might establish a link to Unit 731.

"Our goal is to identify the bones and return them to their families," said Kawamura. He believes the bones are virtually the only evidence of what occurred. We just want to find the truth."

Health Ministry official Atsushi Akiyama has stated that witness accounts have been considered in the 2001 report, and the government's stance is firm. He pointed out that without documentary evidence, such as specimen container labels or official records, it's tough to establish proof.

He noted that documents, particularly those related to Japan's wartime horrors, were meticulously destroyed as the war ended, making the discovery of new evidence challenging. Akiyama also mentioned that the unknown origins of the bones complicate DNA analysis.

Hideo Shimizu, a former lab technician at Unit 731 who attended the meeting virtually from Nagano, recalled seeing human heads and body parts preserved in formalin jars, including a dissected belly with a fetus, referred to as "maruta" - a euphemism for prisoners used in experiments.

Before Japan surrendered on August 15, 1945, Shimizu was tasked with collecting the bones of burned prisoners' bodies. He was given a pistol and cyanide, instructed to commit suicide if captured, and ordered to keep his experiences at Unit 731 secret, avoid contact with former colleagues, and not pursue government or medical positions.

Shimizu expressed his inability to confirm if any of the specimens he encountered at Unit 731 are among the remains found in Shinjuku, based on photographs alone. However, he emphasized the horrors he witnessed in Harbin should never recur. The sight of his great-grandchildren brings back memories of the fetus he saw and the lives that were lost. "I want younger people to understand the tragedy of war," he remarked.