On 4 December Russian forces attacked the Tatars and drove them into the ice fortress, but were defeated trying to take it at once. Princes Pyotr Kuzminsky and Semyon Volynets, who broke into the fortification on the heels of the retreating Tatars, were killed. According to the Russian chronicle, the losses of the Tatars were also heavy, some unnamed Ulug Mohammed's son-in-law was even killed there. Instead of preparing for a coordinated assault, the Russian commanders entered into negotiations and lost their vigilance. In some chronicles, the main blame is assigned to Grigory Protasyev,
voivode of
Mtsensk, who allegedly sided with Ulug Mohammed and "made a treason". Protasyev reported that the Grand Duke wished to conclude peace and did not order "to fight with the Tsar". During the negotiations on the morning of 5 December, Ulu-Mohammed refused to pay him any tribute and promised not to attack the Russian principalities, and offered his son as a hostage. In return, Ulu-Mohammad asked only to be allowed to remain near Belyov until spring. However, voivodes Vasily Sobakin and Andrei Goltyaev, who conducted the negotiations, rejected this proposal. Then Ulug Mohammed, who found himself in a desperate situation, personally led the attack on the Russian army. Taking advantage of the "great mist" the Tatars made the turning movement and attacked from the rear of the unprepared Russian troops. There was panic and total flight, and thus Ulug Mohammed won a complete victory. Gumilev (2024), however, interpreted it as a Tatar defeat. == Aftermath ==