土佐藩
Starting with Inoue Saichiro, who was the shita metsuke (low class inspector of foot soldiers) of the Tosa Domain, Izo assassinated Honma Seiichiro who was his comrade, Ikeuchi Daigaku, Mori Magoroku, Ogawara Juzo, Watanabe Kinzan, and Ueda Jonosuke, who were government officials and yoriki (police sergeants) that belonged to the Kyoto City Magistrate, Tada Tatewaki (son of Nagano Shuzen who commanded Ansei no Taigoku [suppression of extremists by the Shogunate] and Murayama Kazue, who during the assassination was tied to a bridge and made a public display alive). Those killings were conducted in the name of "Heaven's punishment" (天誅, Tenchū), as Takechi called it. Izo became known as 'Hitokiri (man-slayer) Izo' and feared, with a fellow hitokiri Tanaka Shinbei of Satsuma Province.