From New York Times:

 A string of violent attacks by Islamic militants has shattered this city’s reputation as a citadel of religious tolerance and unnerved federal officials in Moscow, who have worked for decades to prevent the spread of radical Islam out of the southern borderlands and into places like this city 500 miles east of Moscow

Officials have long sought to contain Islamic fervor in the Caucasus to the south while insisting that places like the republic of Tatarstan, where Kazan is the capital, were different, representing a moderate “Russian Islam,” said Aleksei Malashenko, the co-chairman of the Carnegie Moscow Center’s religion, society and security program.

But that comfortable assumption began to crumble just before the start of Ramadanin late July, when a senior cleric in charge of education was shot outside his apartment building on Zarya Street. Roughly an hour later, the city’s chief mufti survived a bomb attack that demolished his Toyota Land Cruiser. A previously unheard-of group, the mujahedeen of Tatarstan, claimed responsibility.

On Sunday, a car carrying three men, an automatic rifle and Islamic pamphlets blew up in Zelenodolsk, about a half-hour west of Kazan, in what the authorities described as the inadvertent detonation of a homemade explosive. “That radical direction exists in Tatarstan,” Mr. Malashenko said. “And it’s dangerous.”