Moscow - A Russian judge sentenced protest leader Alexei Navalny to five years in prison on Thursday after convicting him of large-scale theft in a trial Navalny said was politically motivated.
Navalny, one of President Vladimir Putin's biggest critics, was led away from court by law enforcement officers after the judge pronounced the sentence in the industrial city of Kirov. Prosecutors had asked for a six-year sentence.
Navalny had won a rare victory on Wednesday by being accepted as a candidate in a Moscow mayoral election which he had seen as a stepping stone to challenging Vladimir Putin for the presidency.
The activist had been charged with stealing $493 000 from a timber firm.
In a blog posting on Wednesday titled "Before the Verdict", Navalny urged supporters to redouble efforts to challenge the authorities through street protests, electoral politics and efforts to expose corruption.
"We know what to do and how to do it ... the main thing is to take courage, cast off idleness and do it," he wrote.
Navalny's trial had attracted more international attention than any other in Russia since oil tycoon Mikhail Khodorkovsky was jailed in 2005 on tax evasion and fraud charges after falling out with Putin.
Khodorkovsky's $40bn company Yukos was then carved up and sold off, mainly into state hands, and he was convicted of theft and money-laundering in a second trial in 2010.
Tall and clean-cut, Navalny has captured the mood of urban youth disillusioned by Putin's long rule.
But he has also been dogged by accusations that he has nationalist tendencies and his appeal is limited outside the big cities.
"On the one hand it doesn't seem elegant to lock your political opponent behind bars, but I am sure he is no angel anyway," Yekaterina, a businesswoman in Kirov who declined to give her full name, said before the vedict.
Sergei, a Kirov pensioner, said: "I don't think he stole a thing but the problem is that he wants to run for mayor now, then maybe for governor or even president, so this trial is simply meant to close this chapter once and for all."
A thorn in Kremlin's side
Navalny was accused over his role as adviser in 2009 to a timber company that went bankrupt in Kirov, where he was an aide to the liberal regional governor. He denies the charges.
He has long been a thorn in the Kremlin's side, in particular by helping organise rallies which in late 2011 and early 2012 became the biggest protests since Putin rose to power in 2000. However, they have since faded.
Navalny has suggested Putin ordered the trial to silence his criticism of what he calls a political class of "swindlers and thieves" and the absence of the rule of law in Russia. The Kremlin says it does not interfere in criminal cases.
The verdict bars him from running for mayor against Sergei Sobyanin, a Putin favourite, and from contesting the presidential election in 2018, in which Putin, Russia's dominant leader for 13 years, could try to extend his rule until 2024.