Russia's leading online social network was briefly banned on Friday, in a move dismissed as a "mistake" but which follows intensifying official pressure on the company as President Vladimir Putin consolidates his power.
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VKontakte (www.vk.com), Europe's largest homegrown social network with 210 million registered users, was put overnight on a "black list" of sites barred from distributing content inside Russia. Hours later, the ban was lifted.
The company's founder Pavel Durov has clashed with the authorities in the past for providing a forum for opposition activists to organise protests against Putin.
"This happened by mistake," said Vladimir Pikov, a spokesman for Roskomnadzor, the state communications regulator.
"In this case, someone checked a box against the address of the social network. The site has been removed from the list and restrictions on access to it have been lifted."
Durov, 28, founded VKontakte in his native St Petersburg in 2006 and his success in building the network - which attracts 47 million users daily who log on to share news, views and photos - has drawn comparisons to Facebook's Mark Zuckerberg .
Durov refused to comply with an order by the Federal Security Service, a successor to the Soviet-era KGB, to close groups used by activists to organise protests over the December 2011 parliamentary election, which handed victory to Putin's ruling United Russia party.
Last month, he was implicated in a traffic incident in the city of St Petersburg in which a policeman was slightly injured.
Durov has denied being involved in the accident but, instead of agreeing to testify as a witness, he left the country, say sources who know him. He has not been seen in public or posted on his VKontakte page since April 24.
The executive's difficulties coincided with a change of ownership at the company, in which a private equity fund with Kremlin connections bought a 48 percent stake from the founding partners who backed Durov.
The day before the deal closed on April 17, VK's office and Durov's home were searched by investigators.
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