三月事件
As Minister of War (1924–27, 1929–31), Ugaki had overseen a reduction in size and modernization of the army. He had also failed to back the March Incident plotters (who had hoped to make him Prime Minister). Minami, Muto, Nemoto and Katakura were all prominent members of the Tōsei-ha faction. Katakura was also partly responsible for reporting the Military Academy Incident. When Isobe encountered him outside the Ministry of War later that morning, he shot him (non-fatally) in the head.