Tens of thousands of people have rallied in central Moscow in the biggest popular challenge yet to Russian Prime Minister Vladimir Putin's hold on power.<br /><br />Protesters were demonstrating on Saturday against alleged vote rigging in a December 4 parliamentary poll.<br /><br />They were chanting slogans against Putin's United Russia party, with many shouting "Russia without Putin".<br /><br />Protests also took place in St Petersburg - Russia's second city - where thousands of people gathered, and in other cities.<br /><br />Al Jazeera's Neave Barker reports from Moscow, the Russian capital.
