Kazan gang

The Kazan phenomenon (Russian: Казанский феномен) was a term used by journalists to describe the rise in street gang activity in the city of Kazan in the RSFSR and later, the Russian Federation.

From the early 1970s, Kazan had a particularly bad reputation for juvenile delinquency, and a substantial portion of young males in the area of both Russian and Tatar background joined youth gangs, which fought amongst each other for territory, principally using improvised or melee weapons (firearms are not as widespread in Russia and are hard to come by). The crime wave caused a moral panic amongst the Soviet population, as not only was such criminality traditionally seen as a product of the capitalist West, but it also involved the children of local officials.

During the rise of the Russian mafia in the late 1980s and 1990s, the street gangs grew into more sophisticated and organised criminal enterprises. Due to the lack of profitability in running protection rackets in Tatarstan, the Kazan gangs started to move to St Petersburg, where they got into conflict with the local Tambov gang. The Kazan mafia was known to be particularly cruel in their extortion tactics, and periodically brought in reinforcements from Tatarstan. The Slavic gangsters of the city banded together to fight this emerging threat, and eventually forced the Tatars out of St Petersburg.

...
Wikipedia