Moscow: Thousands of protestors on Saturday hit the Russian streets spread over nine time zones even as at least 45 people were detained for taking part in rallies against last Sunday's Duma polls won by Prime Minister Vladimir Putin's ruling United Russia party allegedly through ballot rigging.

Protestors, many with children are converging at two rallies in downtown Moscow, one of which has been banned by the authorities, who have vowed to crack down in case of violation of public law.

The Kremlin and adjoining Red Square have been cordoned off by the heavily reinforced interior troops and riot police.

The Interior Ministry said a total of 45 people have so far been detained across Russia for taking part in unsanctioned rallies and violating public order so far as the protestors converge for the rally in Moscow's Bolotnaya Square.

The state-controlled channels have blacked out the news about the protest rallies and people are using the opposition websites.

A channel reported that at least 20,000 people were present at the Bolotnaya Square near the Kremlin across the river Moskva diving the city.

Interfax reported that protests in the Urals city of Perm attracted several dozen people followed by minor public disturbances which ended with 15 detentions.