BEIJING, July 22  -- Japanese World War II officer Mio Saito's written confession, which was published Tuesday, reveals that Japanese aggressors used Chinese people for live bacteria testing and poison gas testing.

According to the original document, available at the website of the State Archives Administration (SAA), in August 1939, his subordinates received 90 Chinese who were sent from Hebei.

Saito wrote that according to Senior Captain Shirahama's report afterwards, 30 people were for live-body bacteria tests, and the other 60 were for special demonstrations of poison gas shell effectiveness conducted by Ishii Unit in connection with the Narashino School (the gas unit) in Sunwu.

Saito's positions included unit commander of Changchun Branch of the Kwantung Army Military Police in northeast China and captain of Japanese Expeditionary Military Police in South China.

According to the confession, his other crimes also included ordering the transport of 30 Chinese "to the execution ground 20 kilometers to the northeast of Xinjing" in early November 1937 and had them killed.

He also recalled 200 searches in Guangzhou City and nearby villages from August 1940 to June 1942. According to his confession, during the searches,"about 1,000 Chinese were detained, 200 were arrested and 40 of them, or one fifth, were sentenced to severe punishment."

From June 1941 to June 1942, Saito "ordered the Guangdong Military Police three times to have the captured Chinese people severely punished, i.e. killed (by shooting)." The total number was about 120.

This is the 20th confession among a total of 45 Japanese war criminal confessions the SAA plans to publish. The SAA has been issuing one a day since July 3.

The move follows denials of war crimes by Japanese Prime Minister Shinzo Abe and right-wing politicians.