The number of extremism cases launched in Russia surged by 28 percent in 2014, the head of the Investigative Committee said Thursday.
"In the past year, 591 cases were opened for crimes of extremism, which is 28 percent more than in 2013," Alexander Bastrykin said in comments carried by legal news agency RAPSI.
Russia's law prohibiting extremism, first enacted in 2002, has courted a great deal of controversy. Critics say the vague definition of "extremism" allows law enforcement authorities to arbitrarily use it against political opponents and opposition activists.
In 2014, Russian authorities banned 2,241 materials as extremist, according to a report by the U.S. Commission on International Religious Freedom.
Many of the texts deemed to be "extremist" were certain translations of the Quran, as well as texts of the Jehovah's Witnesses.
Some opposition-minded news publications have also been hit with extremism warnings by Russian prosecutors, a move activists have warned is meant to silence criticism of the government.
In mid-October, the Novaya Gazeta newspaper was warned by Russia's media watchdog to delete "extremist" material from its website within 10 days or face its website being blocked. The material in question was an article comparing the policies of Russian lawmakers to those of Nazi leader Adolf Hitler.
In accordance with the extremism law, any media outlet that receives two written warnings within a year can have its media license revoked.