Following the surrender of Allied forces in Singapore, Nishimura was in charge of the eastern half of Singapore Island, during the period in which the Sook Ching massacre took place. Nishimura himself was often at odds with the commander of the 25th Army, General Tomoyuki Yamashita, at times engaging in conduct that seemed deliberately insulting. As a result, his division was denied the Emperor's Victory Citation, and he was recalled to Japan and forced to retire in April 1942.