In 1561 Ujizane ordered his vassal Shizuzane OHARA, who was jodai (vassal who manages the castle while the lord is not in the castle) of Yoshida-jo Castle (Mikawa Province), to kill the hostage from the Matsudaira (Tokugawa) side at the entrance of Ryunen-ji Temple located under the castle.
永禄4年（1561年）に家臣の吉田城(三河国)代小原鎮実に命じ、松平（徳川）側の人質を城下の龍拈寺口で殺した。