According to the written confession of Ryusuke Sako in December 1954, he was born in Yamaguchi Prefecture, Japan in 1892. In November 1934, he went to northeast China to take part in the War of Aggression against China, serving successively as section chief of Inspection Department of the Railway Security Police Forces of the "Manchukuo" and major general and brigade commander of Railway Security Forces in Jilin and Mudanjiang. He was arrested in August 1945.

Major offences:

August 1941:"we captured about 60 Chinese patriots""near Huodoushan along the Jin-Gu Railway" and "sentenced two of them to death penalty";

After 1941:"assisted in household reorganization work along the railways, and the houses of about 3,000 households were ruined";

From December 1941 to March 1942:ordered the arrest of "a total of 39""underground anti-Japanese operators", "verdict: patriot Yang Bailong was sentenced to death, Zhou Zhenhuan life imprisonment and others fixed-term imprisonment";

March 1943: "arrested about 150 Chinese people in Xiabai City and transferred 100 of them to the Chengde Procuratorate";

"During my term in Jinzhou", I ordered the subordinate railway security forces to "conduct the weekly intelligence search" and "arrested a total of more than 3,000 people";

Took part in the meetings of "Southwest Defense Committee", and participated in planning and implementation of "public order" actions such as "arresting, suppressing," and "household and village reorganizing".