What does Maruta mean?

"Maruta" refers to Russian, China and Mongolian prisoners arrested by the Gendarmerie of the Kwantung Army and Harbin Correctional Institution, who are affiliated to the secret service and are said to include Koreans. Then they were sent to the special prison of the 73 1 Army, where they lost their human qualifications and became "maruta" ("maruta" means material in Japanese). When they are recorded in various experiments, the words "♀ maruta" or "♂ maruta" are marked on the form only according to their gender. These two symbols are the special terms used in No.731Military to represent experimental materials. On average, three "maruta" will be consumed in two days.