The wife of opposition leader Alexey Navalny was detained Sunday in Moscow, according to the Navalny team, as she joined protesters across the country in rallying in her husband's name.

“Yulia Navalnaya was detained at the protest! Freedom for the Navalnys!” said a tweet from Navalny's team.

According to OVD-Info, an independent site that monitors arrests, 2,291 people have been detained so far across Russia over the unsanctioned protests, including 520 in Moscow and 242 in St. Petersburg. The total number is expected to increase.

Supporters of Navalny, who's now been in custody for two weeks, said they were planning protests in at least 120 cities across the vast country, starting at noon local time in each location.

Protesters in Moscow planned to march down to the Matrosskaya Tishina detention centre where Navalny is being held in custody, according to a CNN team on the ground. Local authorities were closing metro stops one after another leading up to the detention centre in the city's northeastern Sokolniki neighbourhood.

Before her reported detention, Yulia Navalnaya posted a picture on Instagram showing her taking part in a protest in the area. “It's great in Sokolniki today!” Navalnaya said in the caption, alongside a photo showing her, hands raised, followed by a column of people.

Navalnaya was detained by police officers who did not identify themselves or provide any reason for the detention, according to Vyacheslav Gimadi, head of the legal department of Navalny's Anti-Corruption Foundation (FBK).

“Yulia Navalnaya was detained by the police during a peaceful walk in Moscow. The defence attorney was not allowed to see her, [the police officers] did not introduce themselves, did not show any IDs, did not provide any reason for the detention,” Gimadi tweeted.

Navalny was detained on January 17, moments after arriving in Moscow, following months of treatment in Germany after being poisoned in August 2020 with nerve agent Novichok. He blamed the poisoning on the Russian government, an allegation the Kremlin has repeatedly denied.

The politician is currently in custody ahead of a court hearing on February 2 where a court will decide whether his suspended sentence on fraud charges in a 2014 embezzlement case should be converted into a jail term due to what Russian authorities say is the violation of the terms of his suspended sentence.

On Thursday, Navalny appeared by video link from Matrosskaya Tishina at a court hearing at which his appeal against his detention ahead of next week's hearing was rejected.

Speaking at that hearing, Navalny urged protesters to keep coming out. “They are the last barrier that prevents those in power from stealing everything. They are the real patriots,” he said. “You will not be able to intimidate us — we are the majority.”

Live video feeds and social media videos Sunday showed crowds of people gathering in a number of cities, chanting “Putin is a thief,” in reference to Russian President Vladimir Putin.

In the Russian city of Novosibirsk, in Siberia, live video showed police detaining drivers who were honking their car horns in support of the protesters. In response, demonstrators were heard chanting: “Let them go!”

People could be seen with their elbows linked, forming chains, chanting “Freedom!” and “Give back our money!” as they stood in front of the city hall in the centre of Novosibirsk. Rows of riot police were standing in front of them.

Protesters marching along the snowy streets could be heard chanting: “Russia without Putin!” and “one for all, and all for one.”

Russia's Ministry of Internal Affairs earlier warned Russian citizens not to take part in the “unauthorized” protests. “The Ministry of Internal Affairs of Russia calls on citizens to refrain from participating in unauthorized protests,” the ministry said in an Instagram post.

Russian federal law requires organizers to file an appeal with local authorities at least 10 days in advance to obtain permission to hold a protest.