Russian's most widely known opposition leader Alexei Navalny, along with hundreds of his supporters, were detained Saturday as street demonstrations unfolded in Moscow and 90 other Russian cities to protest Vladimir Putin's inauguration for a fourth presidential term.

Within minutes of Navalny arriving at the protest in central Moscow, he was arrested along with his ally Nikolai Lyaskin. The independent monitoring group OVD-Info estimated more than 350 people had been detained nationwide by police, who dubbed the protests "unsanctioned."

In the hours before his appearance, Navalny — barred from running in April’s presidential race — stayed at a secret location to avoid being detained before he managed to reach the protest held in Pushkinskaya Square. He was dragged off by his arms and legs to a van by five policemen as protesters chanted, “Russia without Putin” and “Down with the Tsar”.

A nationalist youth movement organised a counterprotest in Moscow, attempting to block Navalny’s supporters from gaining access to Pushkinskaya Square.

Although observers expect the anti-Putin protests to be on a smaller scale than in 2012, the Kremlin appears to be planning a more low-key inauguration than previous ones and Putin is likely not to venture beyond the Kremlin complex.

Navalny, who has been repeatedly detained over the years for organising anti-Kremlin protests, urged supporters all week with online messages to protest Saturday, saying “If you think that he’s not our tsar, take to the streets of your cities. We will force the authorities, made up of swindlers and thieves, to reckon with the millions of citizens who did not vote for Putin.”

One activist told a crowd in the city of Khabarovsk, “Putin has already been on his throne for 18 years! We've ended up in a dead end over these 18 years. I don’t want to put up with this!"

In St. Petersburg, anti-Putin protesters were prevented from reaching the city’s central square.

Russian police detain protesters at a demonstration against President Vladimir Putin in Pushkin Square as Russians angered by the impending inauguration of Vladimir Putin to a new term as the country’s president demonstrated throughout the country on Saturday.

Russian police detain protesters at a demonstration against President Vladimir Putin in Pushkin Square as Russians angered by the impending inauguration of Vladimir Putin to a new term as the country's president demonstrated throughout the country on Saturday.

In Yekaterinburg in the Urals, 1,500 kilometres from Moscow, local reporters estimated that about 1,000 people turned out to protest. There also were reports of protests in Siberian towns. Monitors reported that police arrested about 150 people in Krasnoyarsk, in eastern Siberia, and another 75 in Yakutsk.

In the March election, Putin, who has been either president or prime minister since 1999, won against seven weak challengers with almost 77 percent of the vote. It was the largest margin by any post-Soviet Russian leader, which the Kremlin argues demonstrates his “father-of-the-nation” status and his clear mandate to govern.

One of Putin’s challengers, however, described the voting as a “filthy election.”

International observers criticised the poll, saying there had been no real choice in the election and complained of widespread allegations of ballot rigging amid reports of hundreds of ballot violations at polling stations across the country. Russian election officials described the violations as “minor”, but said they were investigating.

Despite Putin’s overwhelming election win, Monday’s inauguration ceremony will be a simpler affair than his previous three swearing-ins. The Russian TV station Dozhd reported Saturday that Putin will forgo driving in a presidential motorcade through central Moscow, avoiding the awkward scenes in 2012, when the capital's streets appeared almost empty.

During Monday's inauguration, Putin will stay within the Kremlin's grounds, taking his oath of office in the Andreyevsky Hall. He is due to step outside the hall to thank party volunteers who worked on his election campaign.

In an effort presumably, to head off Saturday's protests, Russian police raided the homes of Navalny's supporters on Friday and detained dozen.

“Activist Ilya Gantvarg was detained in St. Petersburg last [Friday] night,” said an Open Russian Foundation press release reported by Interfax.

The Open Russia document also says one of its own members, Viktor Chirikov, was detained in the city of Krasnodar, and that an employee of Navalny's staff was detained in her own backyard in Krasnoyarsk.

“She was taken to a court right from home ... tentatively [to be charged] in connection with the May 5 action,” the group said.

In a recent interview with VOA's Russian Service, Leonid Volkov, Navalny's chief of staff, had warned that a crackdown was imminent. “The authorities have been and continue to be afraid of protests. They are trying everything they can — threats, warnings, promises to shatter [the opposition] — it's always the same,” he said.

"Politically speaking, they just can't afford to have a large-scale protest in Moscow," he said.

Navalny's regional headquarters in the Urals city of Yekaterinburg were raided early Friday. Police confiscated promotional materials to be used at Saturday’s rally.

According to a report by Radio Free Europe, a Navalny organiser in the southern city of Volgograd Tweeted that local students were “forced to sign papers acknowledging that they could face serious consequences, including expulsion if they take part in the rally.”

Navalny, who organised massive street protests to coincide with Putin's 2012 reelection, was barred from the presidential ballot due to a conviction on financial-crimes charges he contends were fabricated. (VOA)

•VOA Photo shows Russian police carrying struggling opposition leader Alexei Navalny, centre, at a demonstration against President Vladimir Putin in Pushkin Square in Moscow, Russia, Saturday, May 5, 2018.

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