Moscow (CNN)Around 200 opposition activists were detained in Moscow on Saturday, according to a statement from Russia's Ministry of Internal Affairs.
The detentions are the latest in a series of crackdowns sustained by members of the opposition following Kremlin critic Alexey Navalny's arrest and imprisonment.
Navalny was detained in January on his arrival from Germany, where he spent five months recovering from Novichok poisoning he blamed on the Russian government. The Kremlin has repeatedly denied any involvement.
On Saturday, municipal deputies from Russia's regions gathered in the Russian capital to discuss parliamentary and local elections -- which are scheduled for September -- at a forum held by United Democrats, a project aimed at supporting competitive election, according to their website.
Opposition activist Ilya Yashin said 40 minutes into the event, police broke up the forum and detained around 150 deputies.
"A very symbolic end to a short forum: deputies in police vans, and masked police are twisting people's arms," Yashin said on Facebook.
"But nobody promised us the freedom on a silver platter. Russia will be free anyway," he added.
Yashin also posted images on Twitter of the moment he was taken away from the forum by police and from inside the police van.
Anastasia Burakova, a coordinator of United Democrats told Russian state media RIA Novosti that the forum was held at the Izmailovo Delta Hotel, where municipal deputies from all over Russia gathered to discuss the strategy for the next electoral cycle and share their experiences with each other.
"Everyone was detained who took part both as a listener and as a speaker. No reason was given," Burakova told RIA Novosti.
In a statement, Russia's Ministry of Internal Affairs said that around 200 people had been detained, citing a breach of coronavirus restrictions.
"In one of the hotel premises in Izmailovsky Highway, a group of residents, representatives of a public organization, made an attempt to hold a public event in violation of the established sanitary and epidemiological requirements -- a considerable part of the participants did not have personal protective facilities," the Interior Ministry statement said.
The statement added that "besides, members of an organization whose activities are recognized as undesirable on the territory of the Russian Federation were identified among the participants," and that police stopped the "illegal actions."
Prominent activist and Kremlin critic Vladimir Kara Murza -- a longtime colleague and friend of assassinated opposition figure Boris Nemtsov -- was listed among those detained.
Murza, who says he was poisoned in 2015 and 2017, is the Chairman for the Boris Nemtsov Foundation for Freedom, a group committed "to the spread of education, freedom, and progressive development," according to its website.
OVD-Info, an independent monitoring group, said at least 180 people had been detained.
For months, opposition activists have been met with a harsh show of force, demonstrated most clearly on January 31, when over 5,000 people were detained during nationwide protests in 85 cities in support of Navalny.
The Ministry of Internal Affairs said that "checks are being conducted" on the activists detained on Saturday, and that "a decision will be undertaken in compliance with the law."