In addition, when Ryoma SAKAMOTO was assassinated in October of the same year, he exerted himself in searching for assassins and communicating with Kaientai (association of masterless samurai organized by Ryoma), a trading company, and Rikuentai (the anti-shogunate army of masterless samurai organized by Shintaro NAKAOKA).
また、同年10月に坂本龍馬が暗殺された際には、犯人捜しや海援隊(浪士結社)・陸援隊との連絡等に奔走した。