In the "Double Tenth" trial, 21 members of the Kempeitai (Japanese military police) were accused of war crimes relating to the torture of 57 of prisoners (including John Leonard Wilson, Bishop of Singapore) following a raid on Changi Prison on 10 October 1943 to investigate of a suspected spy network, thought to be responsible for the sinking of seven Japanese merchant vessels in Singapore harbour in September 1943.
He spent two years in Japanese prisons in the hands of the Kempeitai (Japanese military police).
Kempeitai used several as transports in secret and paramilitary operations in Manchukuo.
During the Japanese occupation of Hong Kong, the building served as the Kowloon headquarters of the Kempeitai.
Later he was forced to help the Japanese military police as an interpreter when it was discovered that he was one of the few "locals" in the area who could speak Japanese.
Other examples of action include the Japanese company led by Captain Yamada that had to fight their way into Magelang to assist the British; Japanese Kempeitai (military police) used to guard camps in Buitenzorg, Japanese artillery units used for offensives in Bandung, and the Bandoeng garrison that was reinforced by 1,500 armed Japanese.
Kempeitai officers were trained at special training schools, with the main ones being in Tokyo and Keijo (now Seoul) in Korea.
Its main function was as a civilian counterpart to the military's Kempeitai and Tokkeitai, and it can be considered roughly equivalent to the Federal Bureau of Investigation in the United States in terms of combining both criminal investigation and counter-espionage functions.