Masakado's master, the Daijodaijin (Grand minister of state), FUJIWARA no Tadahira, decided to investigate the truth of the matter, and to that end, issued a migyosho (a document for informing people of the decision of Third Rank or upper people) and sent an emissary to the eastern provinces.
将門の主人の太政大臣藤原忠平が事の実否を調べることにし、御教書を下して使者を東国へ送った。