Unit 516 Archives Reveal New Evidence of Japanese War Crimes
On July 5, 2026, the Exhibition Hall of Evidences of Crimes Committed by Unit 731 of the Japanese Imperial Army in Harbin, Heilongjiang Province, publicly released the “Personal Statement Records” (身上申告书) of Unit 516 — the Japanese Kwantung Army Chemical Department. The 148-page archive, obtained through cross-border evidence collection from Japan in recent years, contains personal information on 108 members of Unit 516 and provides what Chinese authorities describe as irrefutable new evidence of the Japanese Imperial Army’s chemical warfare crimes during its invasion of China, as reported by Xinhua News Agency.
Context: What Was Unit 516?
Unit 516, officially known as the Kwantung Army Chemical Research Institute, was a top-secret Japanese chemical weapons facility operated by the Imperial Japanese Army in Qiqihar, Heilongjiang Province. Established in August 1939, it served as the chemical warfare counterpart to the more widely known Unit 731, which focused on biological warfare and human experimentation. The unit produced mustard gas, lewisite, cyanic acid, phosgene, and diphenylcyanoarsine, and conducted live human experiments throughout its operational period from 1939 to 1945.
According to People’s Daily, the newly released Personal Statement Records cover 108 members of Unit 516, including military personnel, technical officers, medical officers, veterinarians, and chemical soldiers. The documents detail each member’s military transfer history and post-war demobilization records.
Key Findings from the Archives
Jin Shicheng (金士成), a researcher at the Unit 731 Evidence Exhibition Hall, explained that comparing the 108 newly identified individuals with the previously known “Stay-Behind Roster” (留守名薄) revealed 17 duplicates. The total known Unit 516 personnel now stands at 505, providing researchers with a substantially more complete picture of the unit’s scale and organization.
“These archives, from the perspective of personnel transfers, prove that within the Japanese Imperial Army, through mutual personnel transfers and technology sharing, they constructed an integrated biological-chemical warfare network covering ‘humans—animals—environment,’” Jin said, as quoted by Xinhua.
The archives document personnel transfers between Unit 516, Unit 731 (biological warfare), and Unit 100 (veterinary biological warfare), revealing an integrated biological-chemical warfare network. Records explicitly mention members engaged in “research experiments” and work related to “gas” (瓦斯/毒气), directly confirming Unit 516’s chemical weapons development and field testing.
Evidence of State-Organized Crime
Industry experts consulted by Chinese state media concluded that the Personal Statement Records confirm Unit 516’s frequent operational interactions with the Japanese Army Science Research Institute and the Army Medical School. More significantly, the archives prove that Japanese chemical warfare was a top-down organized state crime integrating research and development, training, and logistics.
As China Military (81.cn) reported, the archives also reveal the post-war trajectories of Unit 516 members. After Japan’s surrender in August 1945, 55 members remained in China, while 49 were captured by Soviet forces and taken to the USSR. Before surrender, Unit 516 destroyed its facilities and dumped chemical agents into the Nen River, leaving a toxic legacy that continues to pose safety risks in China to this day.
Archival Diplomacy and Geopolitical Implications
The strategic timing and manner of this disclosure reflects what analysts term “archival diplomacy” — Beijing’s method of using historical evidence to exert moral and political pressure on Japan. According to analysis from China Daily Brief, by meticulously documenting wartime atrocities through state media channels, China seeks to counter historical revisionism in Japan, solidify its role as guardian of regional historical truth, and maintain a check on Japan’s defense modernization and regional ambitions.
The release comes at a time of heightened tensions in East Asia, with Japan pursuing significant defense modernization and China emphasizing historical grievances. The archives serve to ensure that Japan’s wartime past remains a persistent factor in contemporary diplomatic relations.
Historical Significance
Unlike general allegations of wartime misconduct, these personnel files provide specific, documented proof of individual involvement in chemical weapons development and testing. The 148-page archive adds 108 newly identified individuals to the historical record, and the confirmed personnel transfers between Units 516, 731, and 100 demonstrate a unified “human-animal-environment” biological-chemical warfare system that was far more integrated than previously understood.
This disclosure follows a previous release in August 2022, when Xinhua first reported on the Unit 516 member roster. The latest release represents a significant expansion of the historical record and makes it substantially harder for historical revisionists to deny or downplay these atrocities.
What’s Next
The release of the Unit 516 archives raises several important questions. The full extent of abandoned Japanese chemical weapons in China remains unclear, and how this new evidence might affect cleanup efforts is yet to be determined. The Japanese government’s response to this latest archival disclosure will be closely watched, as will whether further undisclosed archives still held in Japan may be sought by Chinese researchers.
For now, the Personal Statement Records of Unit 516 stand as a powerful documentary testament to one of the darkest chapters of World War II in Asia — and a reminder that the historical ledger remains open.