Newly examined archives and oral testimonies released by the Exhibition Hall of Evidences of Crime Committed by Unit 731 of the Japanese Imperial Army provide fresh documentation of Imperial Japanese Army biological warfare operations during World War II. According to the museum, the records detail the operational scope of the Hailar branch, also known as Unit 543, which maintained approximately 160 personnel and collaborated on human experimentation in the Inner Mongolia autonomous region.
The disclosures arrive ahead of the anniversary of Japan’s unconditional surrender, which concluded the Chinese People’s War of Resistance Against Japanese Aggression. Museum officials state that the newly surfaced documentation establishes a direct connection between Unit 731 headquarters and its regional branches, detailing methods used to conceal covert military medical crimes.
Hailar Branch Registration Files and Organizational Structure
The newly released archives span 185 pages and record the names, ranks, enlistment dates, duties, transfers, and post-war statuses of 156 members of Unit 543, according to Jin Shicheng, director of the museum’s education and publicity department. The personnel list includes medical officers, medical, and ordinary soldiers, technical staffers, and civilian employees.
According to research highlighted by Jin, the Japanese army utilized deceptive recruitment methods to shield Unit 731’s human experimentation activities from public scrutiny. Personnel were initially enlisted under the guise of regular infantry units—specifically Units 97, 177, and 201. Following three months of training at Unit 731 headquarters, these recruits were transferred to the Hailar branch.
Previous museum findings indicate that Unit 543 operated alongside Units 731, 100, and 516 to conduct large-scale human gas experiments in the Inner Mongolia autonomous region. The newly published records clarify the administrative pipeline that funneled personnel between the main Harbin facility and the Hailar outpost.
Testimony of Former Medical Soldier Hitoshi Tanizaki
Alongside the archival documents, the museum released a 70-minute video recording of oral testimony from Hitoshi Tanizaki, a former medical soldier who served in the Hailar branch. The footage was collected during a 2016 evidence-gathering trip to Japan by museum researchers.
Tanizaki, who joined the Hailar branch in April 1944, detailed practical duties that included field rat capture and bacterial cultivation. According to his testimony, after completing three months of training in bacterial cultivation techniques, he mastered culture medium preparation, apparatus classification, and incubation techniques.
The branch maintained specialized departments dedicated to bacterial cultivation, water toxicity testing, and material management, reflecting systematic preparation for biological warfare as an extension of Unit 731.
Post-War Accountability and Soviet Trials
The newly examined registration documents also track the post-war fate of Unit 543 personnel, verifying the continuation of judicial investigations following the conclusion of hostilities. According to Jin, out of the 156 documented members, 145 were captured by Soviet forces and detained in the Soviet Union.
Four of these detained individuals underwent trials in Khabarovsk between April and September 1950. Museum researchers note that this documentation confirms that Soviet investigation and judicial accountability for Japanese biological warfare crimes extended beyond the public trials held in 1949, forming a verifiable chain of evidence alongside survivor testimonies and official military records.