After Ryoma was assassinated, Mutsu, who believed that the assassination was masterminded by Yasushi MIURA, a feudal retainer of Kishu Domain, raided Tenmaya (an inn) with fifteen comrades of Kaientai (Tenmaya Incident) where Yasushi was staying.
龍馬暗殺後、紀州藩士三浦安を暗殺の黒幕と思い込み、海援隊の同志15人と共に彼の滞在する天満屋を襲撃する事件（天満屋事件）を起こしている。