The Russian assault on Grozny began in early December, accompanied by a struggle for neighbouring settlements. The battle ended when the Russian army seized the city on 2 February 2000. According to official Russian figures, at least 134 federal troops and an unknown number of pro-Russian militiamen died in Grozny. The separatist forces also suffered heavy losses, including losing several top commanders. Russian Defense Minister Igor Sergeyev said that 2,700 separatists were killed trying to leave Grozny. The separatists said they lost at least 500 fighters in the mine field at Alkhan-Kala.