Kawata and twenty-one men from the same clan, including Gonemon OTA, Hanroku TAKUMA, and Mototatsu SAZEN, attacked four including Kurobe staying at Honkoku-ji Temple at night on August 17, the day before the Coup and killed three of them and let one of them commit suicide with a sword (Honkoku-ji Temple Incident).
河田は政変の前日8月17日夜、同藩の太田権右衛門・詫間樊六・佐善元立ら21人とともに、本圀寺に宿泊中の黒部ら4人を襲撃し、3人を殺害、1人を自刃させた（本圀寺事件）。