Russian opposition leader Alexei Navalny walked free on Monday after spending 15 days in jail over a rally he led against alleged massive corruption by Prime Minister Dmitry Medvedev.
The anti-corruption campaigner was arrested on March 26 at the largest unauthorised demonstration of recent years in Moscow and found guilty of disobeying police orders.
"Hi everyone," Navalny wrote on Twitter, posting a picture of himself at the offices of his anti-corruption foundation.
Just before his release when his sentence ran out at precisely 2:28 pm local time (1128 GMT) police moved Navalny without warning to a different detention centre, in an apparent attempt to avoid media coverage.
The anti-establishment Kremlin foe was forced to hop on the metro as journalists and supporters were left waiting for him at the location where he had been held across Moscow.
Navalny was among hundreds arrested at the Moscow protest and rallies held the same day in dozens of other Russian cities, with the European parliament among those subsequently urging his release.
- Medvedev rejects 'malarkey' -
In Moscow, police in riot gear detained around 1,000 people, including a significant number of teenagers who grew up under Vladimir Putin's rule.
The political and national mood has shifted since the protests, however, following a deadly bomb attack on the Saint Petersburg metro and the United States' direct intervention against Russia's ally Syrian President Bashar al-Assad
Navalny -- a populist with nationalist anti-immigrant views -- has announced he intends to stand in 2018 presidential polls that Vladimir Putin is expected to contest for a fourth term.
He faces legal obstacles to running for the top job due to a fraud conviction at a trial this year that would bar him from public office.
The 40-year-old rose to fame with fiery speeches at mass protests over Putin's return to the Kremlin for a third term in 2012. He has harnessed the power of social media and YouTube to spread his message.
The latest protests focused on claims by Navalny's team of anti-corruption investigators that Medvedev controls luxury villas and vineyards through shadowy not-for-profit organisations.
The video report has been viewed more than 18 million times on YouTube and prompted wide discussion with mockery over details such as Medvedev's purchase of flashy trainers.
Medvedev finally responded in televised comments on April 4, rejecting the claims as "malarkey."
He accused Navalny of wanting "to try to pull people out into the streets and reach political ends," while following the Kremlin practice of not naming Navalny directly.
Following the protests, Putin accused "someone, some political forces" of trying to advance "selfish interests."
Navalny was fined for breaching rules of organising protests after going ahead with the Moscow protest without permission from the authorities.
Police searched the offices of his anti-corruption foundation and detained staff who were accused of disobeying police and sentenced to up to 10 days.