Novgorod First Chronicle
When they arrived at Saray, Batu Khan sent messengers to Mikhail's camp instructing him to worship according to the laws of the Mongols by bowing to the fires and idols. Mikhail agreed to bow to the khan, but he insulted the Mongol by refusing to obey his command to worship idols. Enraged by the prince's retort, Batu Khan ordered that he be put to death. He was slaughtered by Doman of Putivls, and Fedor his "boyar" was killed after him. The Novgorod First Chronicle, the oldest chronicle reporting his death narrates that their bodies were thrown to the dogs; but as a sign of divine favor, their bodies remained unmolested and pillars of fire hovered over them.