Supporters of the imprisoned opposition leader argue with police, while Moscow cracks down on protests in dozens of cities.

Brawls broke out when supporters of imprisoned Russian opposition leader Alexey Navalny gathered in Khabarovsk on Saturday, despite the authorities taking elaborate measures to contain the demonstrations planned in more than 60 Russian cities.

In Moscow, which usually mobilizes the largest rallies, protesters plan to meet in central Pushkin Square at 2 p.m. (11:00 a.m. GMT) and march towards the Kremlin.

In a post on Instagram, Navalny’s wife Julia said she would join the protest in Moscow. “For me, for him, for our children, for the values ​​and ideals that we share,” she said.

The city’s mayor, Sergei Sobyanin, said the call for rallies was “unacceptable” during a pandemic and warned police to take measures to maintain public order.

Navalny employees in Moscow and other regions were arrested ahead of the rallies.

Navalny, a 44-year-old anti-corruption activist and the Kremlin’s fiercest critic, was arrested on Sunday when he was returning to Russia from Germany, where he had been recovering for almost five months from nerve agent poisoning, on which the government charges.

On Monday, a judge ordered Navalny to be detained for 30 days.

Opposition supporters and independent journalists were approached by police officers with official warnings of protests on Saturday.

Universities and colleges in different regions of Russia have urged students not to participate in rallies. Some say they may be subject to disciplinary action, including expulsion.

Many Navalny allies have expressed their support for the social media rallies this week.

Thousands of videos appeared on the TikTok app, popular with teenagers, which has become an emerging medium for Russians to express their political views.

Russia’s media watchdog warned online platforms against encouraging minors to participate in the rallies or risking heavy fines.

Russia’s most popular social network, VKontakte, blocked groups formed to coordinate protests in different cities.

Navalny faces years of imprisonment. Authorities accused him of violating suspended sentences in a 2014 conviction for financial misconduct, including while he was recovering in Germany.

Following his arrest, his team published an investigation into lavish Black Sea property allegedly owned by President Vladimir Putin, a claim the Kremlin denied.

The two-hour video report has been viewed more than 64 million times since it was released on Tuesday, making it the Kremlin critic’s most-watched YouTube investigation.

Navalny’s arrest drew widespread Western condemnation and the United States, the European Union, France and Canada all demanded his release.