In 1942, Fort Sill held approximately 700 Japanese Americans interned by the Department of Justice — mostly non-citizen Issei who had been arrested as spies and fifth columnists, despite a lack of evidence supporting the charges against them. 350 of these internees were transfers from Fort Missoula, Montana. One of them, Kanesaburo Oshima, was killed by a guard when he suffered a mental break and attempted to escape on May 12. In addition to the Japanese American inmates, Fort Sill held three German prisoners of war.