At least 10,000 protesters marched through the eastern Russian city of Khabarovsk Saturday in support of a popular local governor arrested this week for allegedly ordering several murders.
A court in Moscow on Friday ruled to hold 50-year-old Sergei Furgal for two months pending trial for the murders of several businessmen 15 years ago.
He vehemently denied any involvement.
Furgal's nationalist Liberal-Democratic Party has thrown its weight behind the governor, and on Saturday said "35,000 people came out to the streets" in Khabarovsk to protest his arrest.
But the rally, estimated by various sources to have involved between 10,000-40,000, was clearly fueled by broader anti-Kremlin sentiments too, with people chanting anti-Vladimir Putin slogans.
Local news website DVHab.ru called the rally "the biggest in the history of Khabarovsk," saying the crowds temporarily blocked traffic as they walked through the city of more than 600,000 inhabitants.
Footage showed people shouting "Freedom!" "Moscow go away!" and "Sergei Furgal is our choice" as they walked.
Some held posters saying "We are Sergei Furgal!" Others demanded that Furgal be flown back from Moscow and the charges investigated locally.
The website put the number of protesters between 20,000-30,000, while police estimated about half that, and local supporters of Russian opposition leader Alexei Navalny claimed a figure of up to 40,000.
Navalny and other Kremlin critics in Moscow cheered the turnout. "I'm proud of my compatriots who took to streets demanding fair elections, justice and their right to elect public officials," he wrote.
The demonstrations were unprecedented for almost any Russian city outside Moscow and St. Petersburg, and, though unauthorized, seemed peaceful and took place without police interference.
Smaller rallies were held in other cities in Khabarovsk region, reports said.
Popularly elected in 2018, Furgal embarrassed the ruling United Russia party, securing 70% of the vote.
His sudden arrest came just days after President Vladimir Putin — who has been in power for two decades — won a landslide ballot on constitutional reforms that could allow him to extend his rule until 2036.
Serving or former governors are often prosecuted in Russia. In the past decade, at least 10 governors have been sentenced to prison or are currently under arrest pending trial.
More than 40,000 people have now signed a petition demanding Furgal's release.