He was second-in-command of the IJA 17th Army under General Harukichi Hyakutake during the initial period of the Bougainville campaign, and (as lieutenant general) later took command of the 17th Army after Hyakutake suffered a stroke in 1945.
During the early stages of the Bougainville campaign, he was second-in-command under General Harukichi Hyakutake for the IJA 17th Army. After Hyakutake suffered a stroke and became incapacitated in 1945, he assumed command of the 17th Army.