On April 30 of the intercalary year (old lunar calendar), he attacked Yoshitsune and his less than 20 subordinate warriors at the Koromogawa no Tachi residence of FUJIWARA no Motonari, leading 500 warriors on horseback.
そして閏月4月30日_(旧暦)、500騎の兵をもって10数騎の義経主従を藤原基成の衣川館に襲った。