Descendant of Japanese invader reveals records of germ warfare in China

A descendant of Japanese invaders from the wartime Unit 1644 has come forward with evidence of the Imperial Army's germ warfare in China, shedding new light on atrocities committed during Japan's invasion.

"This is the first time Japan has made public the complete roster of Unit 1644, revealing details about the unit," said 77-year-old Katsutoshi Takegami, son of a member of the unit, in a recent interview with the People's Daily. "The evidence of the crimes committed by the invading Japanese forces in China is solid and undeniable."

Earlier this year, at the request of Takegami and Japanese researchers, the National Archives of Japan released for the first time the personnel rosters of the Imperial Japanese Army's Unit 1644, Unit 8604 and Unit 8609 stationed in China.

These rosters are part of the personnel records of the invading Japanese forces, containing information such as names, dates of birth, registered domiciles and military branches of the unit members at the time. They serve as important primary materials for studying these Japanese military units.

In 2017, while renovating his family's warehouse, Takegami discovered several photo albums and documents left behind by his father. These materials recorded the activities of the Imperial Japanese Army's "Epidemic Prevention and Water Supply Units" in east and central China during the invasion.

Takegami had previously learned from Seiichi Morimura's acclaimed work "The Devil's Gluttony" that the units labeled as epidemic control and water sanitation, which appeared to supply potable water to troops, were in fact covertly conducting biological warfare and human experiments.

Due to strict military secrecy requirements, Takegami's father never spoke to him about his experiences in China during his lifetime. After investigation, Takegami found that from 1932 onward, his father had been to China three times, serving as a medical orderly and in other roles, and in 1941 he was transferred to Unit 1644.

The invading Japanese army launched multiple biological warfare attacks in China, with Unit 1644 among the various units – including the notorious Unit 731 – responsible for such atrocities. Takegami said that while there is considerable information available about his father's service in other units, records about Unit 1644 are very scarce.

Publicly available data show that Unit 1644 was closely linked to Unit 731 in terms of personnel deployment and equipment mobilization. It was involved in developing biological weapons, cultivating pathogens, conducting human experiments, and cooperating with Unit 731 to carry out biological warfare against China. This caused widespread outbreaks of severe infectious diseases such as cholera, typhoid, and plague in provinces like Zhejiang and Jiangxi, inflicting great harm on the local population.

Takegami noted that after Japan's defeat, many related records were destroyed, especially those involving biological warfare and human experiments. The few surviving materials are of great importance to public knowledge, as the truth about Unit 1644 remains largely undisclosed, making these documents particularly valuable.

"I deeply mourn the Chinese people who lost their lives during Japan's invasion of China. Even now, there are still occasional acts and statements in Japan that deny or whitewash the history of aggression. A crime is a crime – we must reflect on it honestly, and the Japanese government should sincerely apologize to China," Takegami said.

"In my lifetime, I will continue striving to reveal the truth of history to the world, so that such tragedies never happen again," he added.