The gang of seven targeted non-Slavic migrants in the city between August 2006 and October 2007.
Many of the attackers were minors at the time. Besides killing 18 people, they also tried to murder another 12, the court heard.
The group posted video of some of their crimes on the internet.
The heaviest jail term was handed to Roman Kuzin, who received 20 years in jail.
The two alleged ringleaders....