On Saturday, the OVD-Info protest monitoring group said at least 212 people had been detained, including 109 in Saint Petersburg and 39 in Moscow, at events on Friday and Saturday.

The federal prison service said that Navalny, 47, fell unconscious and died on Friday after a walk at the “Polar Wolf” Arctic penal colony where he was serving a 19-year sentence, prompting an outpouring of grief and shock among his supporters across the world and condemnation from world leaders.

As news of his death spread, spontaneous memorials took place in several urban areas, with people taken into custody in 21 cities, according to OVD-Info, which tracks political repression in Russia.

The group reported individual arrests in smaller cities across Russia, from the border city of Belgorod to Vorkuta, an Arctic mining outpost once a centre of the Stalin-era gulag labour camps, to Nizhny Novgorod, Krasnodar, Rostov-on-Don and Tver.

“In each police department there may be more detainees than in the published lists,” OVD-Info said. “We publish only the names of those people about whom we have reliable knowledge and whose names we can publish.” The tally could not be immediately verified.

The hundreds of flowers and candles laid in Moscow on Friday for Navalny, a prominent critic of President Vladimir Putin, were mostly taken away overnight in black bags. A few dozen roses and carnations remained in the snow on Saturday at the monument to the victims of Soviet repression, which sits in the shadow of the former KGB headquarters on Lubyanka Square in central Moscow.

Videos and photos shared on Russian social media also showed flowers being cleared from monuments to victims of Soviet-era repression across the country.

Protests are illegal in Russia under strict anti-dissent laws, and the authorities have clamped down particularly harshly on rallies in support of Navalny.

Authorities in the capital said on Friday they were aware of calls online “to take part in a mass rally in the centre of Moscow” and warned people against attending.

On a bridge beside the Kremlin where opposition leader and former prime minister Boris Nemtsov was shot dead on February 27, 2015, flowers were also removed overnight.

A makeshift vase of white and red carnations remained with a small printed piece of paper. “Boris Nemtsov was shot in the back and murdered here,” the note said.

On Saturday, police blocked access to a memorial in the Siberian city of Novosibirsk and detained several people there as well as in another Siberian city, Surgut, OVD-Info said.

Video shared on social media from Novosibirsk showed people sticking red flowers in the snow as police blocked access to the memorial with tape.

Putin’s ties with West

Navalny’s death – which comes less than a month before a presidential election that is certain to return Putin to another six years in power – will have little effect on the results, said Alexey Muraviev, professor of strategic studies at Curtin University.

“Navalny did not have any significant political weight in Russia. He had an army of supporters but compared to the overall proportion of the Russian conservative electorate they were, and continue to remain, a minority,” Muraviev told Al Jazeera.

Instead, Muraviev added, this could harm the Russian president’s attempt to re-establish a dialogue with the West with the renewed focus on his repressive regime.

United States President Joe Biden said Navalny “bravely stood up to the corruption, the violence and all the bad things the Putin government were doing,” adding that “Putin is responsible for Navalny’s death”.

European Council President Charles Michel said the Russian dissident “fought for the values of freedom and democracy” and made the ultimate sacrifice.

“The EU holds the Russian regime for sole responsible for this tragic death,” he said.

Australia’s Foreign Minister Penny Wong on Saturday said Navalny’s “heroic opposition to Putin’s repressive and unjust regime inspired the world”.

Wong posted on X: “We hold the Russian Government solely responsible for his treatment and death in prison.”

The Kremlin – which has not commented on Navalny’s death – has described Western leaders’ reactions as “absolutely unacceptable” and “hysterical”.

China’s foreign ministry declined to comment on Saturday describing it as “Russia’s internal affair”, the AFP news agency reported.

Navalny had been jailed since January 2021, when he returned to Moscow to face certain arrest after recuperating in Germany from nerve agent poisoning he blamed on the Kremlin. He was later convicted three times, saying each case was politically motivated, and received a sentence of 19 years for extremism.

After the last verdict, Navalny said he understood he was “serving a life sentence, which is measured by the length of my life or the length of life of this regime”.

Hours after Navalny’s death was reported, his wife, Yulia Navalnaya, addressed the Munich Security Conference in Germany where many leaders had gathered.

“If this is true, I want Putin and everyone around Putin, Putin’s friends, his government to know that they will bear responsibility for what they did to our country, to my family and to my husband. And this day will come very soon,” she said.

Navalny’s mother, Lyudmila Navalnaya, was travelling to the prison colony where he died, accompanied by his lawyer, the Novaya Gazeta newspaper reported on Saturday.