Ermák believed their oath, and sent forty men under Iván Koltsó. When these forty men came there, the Tartars rushed against them and killed them, so there were still fewer Cossacks left.

Another time some Bukhara merchants sent word to Ermák that they were on their way to the city of Sibír with goods, but that Kuchum had taken his stand with an army and would not let them pass through.

Ermák took with him fifty men and went out to clear the road for the Bukhara merchants. He came to the Irtýsh River, but did not find the Bukharans. He remained there over night. It was a dark night, and it rained. The Cossacks had just lain down to sleep, when suddenly the Tartars rushed out and threw themselves on the sleepy men and began to strike them down. Ermák jumped up and began to fight. He was wounded in the hand. He ran toward the river. The Tartars after him. He threw himself into the river. That was the last time he was seen. His body was not recovered, and no one found out how he died.