May 1188 (April 1188), Yoritomo asked the Imperial Court for inzen to search for and kill Yoshitsune, and an imperial decree to hand over Yoshitsune was issued to Yasuhira.
翌年4月に頼朝は義経追討の院宣を院に求め、泰衡に義経を召し進せよとの宣旨が下される。