Flash forward 21 years to another site a short distance from where the remains were discovered in 1989. Excavation work will soon commence at this second site, one of three identified in 2006 by a former nurse who worked at the Imperial Japanese Army Medical College in Shinjuku, and who pinpointed possible locations where human remains were hastily buried.
These were all probably the unfortunate victims of a string of medical experiments performed on living subjects in Japan as well as in Manchuria and China by the Imperial Japanese Army.
The nurse reported that she and other medical workers were ordered to bury these complete and partial remains after Japan surrendered to the US in August, 1945.
The Imperial Japanese Army Medical College's Research Institute for Preventive Medicine once occupied this site. The infamous Unit 731 created in 1932 - aka the "Kwantung Army Epidemic Prevention and Water Supply Department" or simply the "Manchuria 731st Unit" - was also headquartered there.
Today, a soon-to-be demolished government-funded residential complex is located at the Tokyo compound.
Ishii Shiro, the director of Unit 731 who died in the 1950s, was once described as the "Japanese Mengele", a reference to Josef Mengele, the German SS officer and a physician in Nazi concentration camps who was also known as the "Angel of Death". Unit 731's operations in China included a large contingent in Harbin, along with one in Singapore.
Shinjuku was the source of BW agents that infected thousands of people in China. Estimates of the total death toll in China range from anywhere between 250,000 and 1 million. The BW experiments conducted in Shinjuku and elsewhere which Ishii supervised killed more than an estimated 3,000 people, including many Chinese.
Many of the army officers and personnel responsible for these horrific acts who were captured by the Russians were imprisoned. But in Japan after the war, the US turned a blind eye and allowed them to simply walk away. The perpetrators were never prosecuted or punished in any way.
According to Koga Kei, a 2009-2010 Vasey Fellow from Japan at the Pacific Forum Center for Strategic and International Studies (CSIS) in Honolulu and a PhD candidate in international relations at the Fletcher School of Law and Diplomacy at Tufts University, the upcoming excavation in Shinjuku is tied to the broader joint effort recently undertaken by Japan and China to jointly explore historical issues often divisive and painful in an attempt to gain a better understanding of each other's different perspective, among other things.
Koga remains concerned that given the sensitivity of the subject at hand,
Thanks in great part to the Democratic Party of Japan (DPJ) and the concerted pressure exerted by a particularly persistent and unyielding Japanese civic organization - the Association Demanding Investigation on Human Bones Discovered from the Site of the Army Medical College - Japan's Ministry of Health, Labor and Welfare approved the excavation in Shinjuku.
In effect, this issue is one of many others including a friendlier relationship with China, and a harder line on the US - Japan security treaty that the DPJ has used to distinguish itself from the LDP and that it is now trying to capitalize on.
While there has been a long history of revelations in Japan about wartime Japanese atrocities and while some might argue that the Japanese are very aware of them, many view Japan as moving ahead too slowly and still dragging its feet.
"There has been insufficient Japanese scholarly or governmental investigation of these episodes and this new investigation is long overdue. A large part of Japan's difficulty addressing these issues was that the conservative LDP had in its DNA ties to the pre-war leadership, while the left in Japan had a political agenda that went beyond truth and reconciliation and was therefore suspect from the beginning," said Michael Green, senior adviser and Japan chair at CSIS in Washington, DC.
With the rapid recent rise of the DPJ, more space has perhaps emerged for less politically motivated inquiries that can enjoy broader political support.
"This is not the same Japan," said Green. "And coming at a time of sagging confidence among Japanese citizens about the future, it will be important for the emerging generation of leaders to expose and learn from this tragic history while also instilling pride and confidence in Japan's role in the world."
Japan must prepare for what will surely be an extremely sensitive and perhaps painful episode.
A close friend and former instructor of Chang informed this writer in 2008 that she was unaware that Chang was engaged in any in-depth research focused on Japan's BW program before and during World War II. Still, Chang appeared to know quite a lot about what transpired. She must have known that Unit 1644 established a forward base in Nanjing. Unit 1644 specialized in BW like Unit 731 and conducted extensive BW field operations in China, especially from late 1940 until 1942. China conducted a formal inquiry into one of this unit's BW attacks - on Ningbo in October 1940 - for example.
Decisions made years ago by the Japanese government to undertake government-funded construction projects at these troubling sites are seen by many as no mere coincidence.
Asia Times Online's attempts to contact Tsuneishi were unsuccessful.
Tsuneishi gave a speech at the annual meeting of the Association for Asian Studies last March in Philadelphia entitled,
The truth about the role of Unit 731 in so many BW-related deaths in China and the US government's deliberate attempt to cover up this war crime really did not emerge until the late 1970s and early 1980s. Japanese and American researchers pursued every shred of evidence.
Professor Sheldon Harris at California State University at Northridge stood out early on in this regard.
However, while Harris and others helped to expose the fact that the US secretly decided to overlook the criminal acts perpetrated by members of Unit 731 and not prosecute them as war criminals once the US had obtained the data derived from countless human experiments performed by the Japanese, the fact that the US actually paid Ishii and other members of Unit 731 an enormous sum in order to obtain this data only recently came to light, due to Tsuneishi's diligent research.
There was no mention of any payment from a secret US fund in this 1947 memorandum to US General Douglas MacArthur, for example.
"For all practical purposes, an agreement with Ishii and his associates that information given by them on the Japanese BW program will be retained in intelligence channels is equivalent to an agreement that this [US] government will not prosecute any of those involved in BW activities in which war crimes were committed. Such an understanding would be of great value to the security of the American people because of the information which Ishii and his associates have already furnished and will continue to furnish." 
In Philadelphia, according to one person who was in the audience, Tsuneishi spoke about the many errors that can be found in English publications and books about Unit 731, and he criticized authors for not doing thorough research on this topic. However, while historical inaccuracies and distortions are unwelcome and distracting, this does not excuse the conduct of the Japanese government which bears much if not all of the responsibility for concealing the truth about Shinjuku.
Among other things, the Japanese Health Ministry has repeatedly denied Chinese requests for DNA tests. 
According to Koga, one Japanese Health Ministry official said during the 164th Diet (parliament) session in 2006 that although several DNA investigations were undertaken, sampling was difficult and because a substance known as hormaline might be present in the human bones in question, it would be difficult to reach definitive conclusions. There is no firm indication of any substantive DNA work done prior to 2006 on any remains recovered in Shinjuku.
In late 2010, there might be a change of heart in Tokyo.
While analyzing DNA evidence might reopen the door to another dark dimension of this chapter in Japanese history, it must be done.
What about the American prisoners of war in Shinjuku? Is this file now closed? After all, a quick scan of state and local prisoner of war (POW) accounts from the Pacific theater, for example, has revealed that hundreds of American POWs were held at a POW camp(s) in Shinjuku during World War II for varying lengths of time, and it would have been very easy for the Japanese to conceal their fate.
''It is significant that these are probably the skeletons of non-Japanese,'' said Tsuneishi a short time after the mass grave was discovered in 1989. ''The Health and Welfare Ministry has been very eager to collect bones in the South Pacific islands for decades. I just wish they had that enthusiasm for the mysterious bones here in Tokyo.'' 
1.) WWII horrors believed hidden in Tokyo neighborhood, Taipei Times, September 18, 2006
2) Book Exposes WWII Japanese Biowarfare Program in China, China Internet Information Center
3) Government to excavate Shinjuku site for remains of WWII-era live human experiment victims, July 8, 2010, Mainichi Daily News
4) Memos Say US Hid Japanese War CrimeDecember 18, 1988, LA Times
5) Human bones could reveal truth of Japan's 'Unit 731' experiments February 15, 2010, Daily Telegraph
6) Skulls Found: Japan Doesn't Want to Know Whose, August 13, 1990, New York Times
Peter J Brown is a freelance writer from Maine USA.