According to the Shimotsuki Incident note, the only primary archive describing the incident, when Yasumori was in his second house in Matsutani in the morning of December 21, he noticed a restlessness in the world and went back to his residence in Tonotsuji around midday to prepare to attend court, but he was attacked and killed by Yoritsuna's soldiers when he arrived at Sadatoki's residence.
合戦の状況を語る唯一の一次史料である霜月騒動覚聞書によると、11月17日の午前中、松谷の別荘に居た泰盛は、世間が騒がしくなった事に気付き、昼の12時頃塔ノ辻にある出仕用の屋形に出かけ、貞時邸に出仕したところを頼綱の手勢の襲撃を受けて殺害された。