The Russian government has banned four websites known for their criticism of the Kremlin.
Russia's communications agency has banned Grani.ru, Kasparov.ru, and the online site for "Yezhednevny zhurnal" ("Daily Journal").
The Russian communications agency said the websites are being blocked because they have called for incitement to unlawful behavior and for people to take part in unauthorized gatherings.
In addition, the website of prominent opposition leader Aleksei Navalny has also been banned for violating the terms of the house arrest that Navalny is currently serving.
Kasparov.ru is the website of opposition figure and former world chess champion Garry Kasparov.
Internet service providers in Russia have already begun enforcing the ban.
The website bans were made at the request of the Prosecutor-General's Office.
With reporting by AP and lenta.ru