 From 1932 to 1933, Okamura was Deputy chief-of-staff of the Shanghai Expeditionary Army under the aegis of the Kwantung Army.According to Okamura's own memoirs, he played a role in the recruitment of comfort women from Nagasaki prefecture to serve in military brothels in Shanghai.He served as military attaché to Manchukuo from 1933 to 1934, and played a role in the negotiations for the Tanggu Truce between Japan and China.