BEIJING, Aug. 15 (Xinhua) -- China has received new pieces of evidence on the war crimes committed by invading Japanese troops during World War II (WWII), including letters written during the 1937 Nanjing Massacre and an oral testimony about the notorious biological warfare division Unit 731.
The Memorial Hall of the Victims in Nanjing Massacre by Japanese Invaders, located in Nanjing, capital of east China's Jiangsu Province, collected more than 150 sets of artifacts and historical materials, as well as over 100 pieces of archival documents, in the first half of 2026, the memorial hall said on Saturday, which marks the 81st anniversary of Japan's surrender in WWII.
The newly acquired items, many donated by young students, include private correspondence from Japanese soldiers, battlefield postcards, instructional materials on gas warfare, and compilations of wartime press coverage.
Among them is a collection of private letters written between 1937 and 1939 by a soldier of the Imperial Japanese Army's 16th Division, surnamed Ishikawa. In a letter dated Dec. 20, 1937, one week after the fall of Nanjing, Ishikawa wrote, "A few days ago, we killed over ten thousand defeated soldiers." This letter serves as a firsthand account from the perpetrator himself, recorded at the time of the massacre, and corroborates the diary entries of Azuma Shiro, a fellow soldier in the same division.
Also donated are two instructional manuals on the systematic training of poison gas warfare by the invading Japanese forces.
In addition, Marcus Detrez and Bastien Ratat from France and Zhong Haosong from China made a joint donation of archival materials to the memorial hall. The donated items comprise 861 pages of documents from the French Ministry of Foreign Affairs relating to Japan's aggression in China, as well as over 50 Japanese-language publications, including wartime illustrated magazines and frontline war records.
"These artifacts, historical materials and archival documents reveal the atrocities committed by Japanese forces, including the Nanjing Massacre and other war crimes, from various perspectives. Coming from different sources, they corroborate one another and form an irrefutable chain of evidence," said Meng Guoxiang, a researcher at the Institute for National Memory and International Peace Studies.
On Friday, a new batch of artifacts, photos and video records documenting the experiences of surviving victims of the Imperial Japanese Army's wartime "comfort women" system were put on display at the Nanjing Museum of the Site of the Lijixiang Comfort Stations. Two Chinese photographers donated the historical materials after years of on-the-ground documentation and field research.
Li Xiaofang, a member of the China Photographers Association, spent more than two decades traveling across China, Japan and the Republic of Korea to visit, interview and photograph more than 100 survivors of the "comfort women" system. Among the donated items are more than 200 photographs he took of over 70 survivors, along with 43 replica handprints and around 30 pieces of personal belongings from survivor Yi Yinglan.
"After escaping from the comfort station, I had to take a bath every day, hoping to wash away the humiliation and pain from my body," Li recalled survivor Zhou Fenying telling him. "It was a psychological trauma she could never erase."
Another donor, photojournalist Yan Meihua from Xiaogan City in central China's Hubei Province, devoted two years to recording the testimony and daily life of Mao Yinmei, a Korean-born survivor. Yan eventually compiled more than 7,000 images and 10 video clips, all of which were donated to the museum.
"She often sat alone in silence. Whenever the Japanese military was mentioned, her face would turn pale, and she would quietly shed tears," Yan said. "You could really feel that the scars left by Japan's wartime atrocities never left her, like a shadow that never faded."
A new collection of historical records about Unit 731 was also made public on Wednesday in northeast China, offering further evidence of wartime crimes against humanity committed by the Japanese forces in China.
Released by the Exhibition Hall of Evidences of Crime Committed by Unit 731 of the Japanese Imperial Army in Harbin, capital of Heilongjiang Province, the 70-minute oral testimony from Hitoshi Tanizaki, a former medic at the Hailar branch of Unit 731, confirms that the Japanese military buried large quantities of chemical shells in China on the eve of its defeat. Researchers collected the testimony in 2016 during a visit to Japan.
Tanizaki said that after being assigned to the Hailar branch, he realized that it was a military unit that violated international law. The Hailar branch was under the direct command of Unit 731's headquarters in Harbin. Its First Section cultivated bacteria, while its Second Section conducted toxicity tests on water sources, among other duties.
Tanizaki confirmed that, during the retreat, the Hailar branch set all its facilities on fire, while the Japanese gas unit secretly buried a large number of poison gas shells. "It wasn't bacteria, but poison gas," he said, adding that there was a poison gas unit based in the Fulaerji district of Qiqihar, Heilongjiang.
Jin Shicheng, a researcher at the exhibition hall, said the testimony directly corroborates that the Japanese military had abandoned chemical weapons in China when Japan was defeated. It also sheds light on the historical origins of the postwar harm caused by these abandoned weapons, giving the findings contemporary relevance.
According to China's position paper submitted to the Fifth Review Conference of the Chemical Weapons Convention, abandoned Japanese chemical weapons have caused more than 2,000 casualties in China since the end of WWII.
Jin also introduced the personal information registration files of the Unit 731 Hailar branch, another piece of evidence disclosed to Xinhua on Wednesday. Research into these files exposes how the Japanese military concealed its biological warfare crimes by recruiting personnel under the guise of regular infantry units, a deceptive practice intended to cover up secret criminal activities including human experimentation.
Meanwhile, the records reveal that 145 of the 156 unit members were captured by Soviet forces after the war and detained in the Soviet Union, with four of them tried in Khabarovsk between April and September 1950. Jin said the findings confirm that Soviet investigations and judicial accountability for Japanese biological warfare criminals had continued after the public trials held in 1949.
The expert noted that the disclosed records will deepen research into the branches of Unit 731 and, together with previously obtained oral testimonies from former members, form a solid chain of evidence of Japan's gruesome WWII war crimes.
Unit 731 was a top-secret biological and chemical warfare research base that served as the nerve center of Japan's WWII biological warfare operations in China and Southeast Asia. At least 3,000 people were subjected to human experiments conducted by Unit 731, and Japan's biological weapons claimed more than 300,000 lives in China.
"Today, the international community has largely reflected on Nazi Germany's medical crimes and the Doctors' Trial during the Nuremberg Trials. However, the awareness of Japan's wartime medical atrocities remains insufficient," said Yang Yanjun, a researcher at the exhibition hall.
Yang called on scholars worldwide to further enhance the academic rigor and objectivity of studies on the crimes committed by Unit 731, and help foster a correct historical understanding in the international community. ■
