|Anti-corruption blogger Alexei Navalny, right, was detained during a mass protest in Moscow [Reuters]
Russia has released a high-profile blogger and other opposition activists after they served 15-day prison terms for taking part in an unsanctioned rally protesting election results.
Alexei Navalny, who has become a figurehead for the opposition, was freed from a police station in Moscow early on Wednesday, the Solidarnost (Solidarity) opposition movement said.
The 35-year-old was greeted by chants of "Navalny, Navalny" and applause from his supporters.
Navalny's blog examining alleged corruption at state companies was seen as a key influence on demonstrators who protested against alleged vote rigging in parliamentary elections earlier this month that handed victory to Vladimir Putin's United Russia party.
He was detained on December 5 during an opposition protest in central Moscow attended by thousands of people.
Also freed was opposition leader Ilya Yashin who was arrested at the same time as Navalny. Another 10 activists who took part in the protest were also freed, Solidarnost added.
Navalny used his release from jail to call on Russians to unite against Putin whom he said would try to snatch victory in a March 4 presidential election that was sure to be unfair.
"For Putin to leave, we must put forward our completely legal demands. So that Putin leaves, we don't need to smash up and burn shops or anything like that; people should come out and show their will, show that they are the power," Navalny said.
"What will happen on March 4 will not be presidential elections in the normal sense of the word so it is pretty senseless to take part," he said, though he added that if free elections were held he would "be ready" to run.
"I am not afraid. We are the majority, we are the power in this country and we see their fear, we feel their fear," he said.
Navalny called on people to join mass protests planned for Saturday across Russia to call for free and fair elections. Russian authorities have sanctioned a protest of up to 50,000 people in Moscow.
"The party of swindlers and thieves is putting forward its chief swindler and its chief thief for the presidency," Navalny said.
His 'swindlers and thieves' slogan has struck a chord with opposition activists, turning him into the most prominent leader of the fragmented dissident groups which refuse to co-operate with the Kremlin.
Putin, who served as Russian President from 2000 to 2008, is almost certain to win the presidential election and his ruling party dismisses Navalny's slogan.
Putin supporters, who credit the 59-year-old with bringing order to Russia after the chaos that followed the 1991 collapse of the Soviet Union, say the opposition movement represents a tiny section of Russia's 143 million population.