The launch ceremony for two new books on the crimes of Unit 731 is held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Wang Song)

The launch ceremony for two new books on the crimes of Unit 731 is held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Zhang Tao)

This photo shows books on the crimes of Unit 731 during a launch ceremony held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Wang Song)

Researcher Yang Yanjun introduces details of new books on the crimes of Unit 731 during a launch ceremony held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Zhang Tao)

The launch ceremony for two new books on the crimes of Unit 731 is held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Zhang Tao)

The launch ceremony for two new books on the crimes of Unit 731 is held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Wang Song)

A reader reads a book on the crimes of Unit 731 during a launch ceremony held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Wang Song)

This photo shows two new books on the crimes of Unit 731 during a launch ceremony held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Zhang Tao)

This photo shows books on the crimes of Unit 731 during a launch ceremony held at the Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army, in Harbin, northeast China's Heilongjiang Province, Sept. 17, 2025. The two books, with the latest research covering transnational verification, oral histories, and multilingual archives, record the crimes of Unit 731 and expose Japan's wartime atrocities. (Xinhua/Zhang Tao)