Russian authorities searched the homes of artists and activists in several cities on Tuesday in connection with the case against a former member of the Pussy Riot protest group fighting on the side of Ukraine, AFP reports.

Over the past two years, the Kremlin has carried out a large-scale crackdown on all forms of dissent, and the raids came just days before the March 15-17 presidential election.

According to human rights organizations and independent Russian mass media, a dozen artists were searched on Tuesday in connection with a new case related to the former member of the Pussy Riot protest group and the founder of the Mediazon publication Pyotr Verzilov.

According to the news site, which specializes in Russian court cases, the searches took place in Moscow and St. Petersburg, as well as in other major cities such as Nizhny Novgorod, Yekaterinburg, Ulyanovsk and Samara.

The non-governmental organization “OVD-Info” reported that Russian special services (FSB) interrogated Pussy Riot member Olga Pakhtusova and artists Oleksandra Katsiko and Vladlena Milkina.

Piotr Verzilov claims to have fought alongside Kyiv forces in Ukraine after being expelled from Russia.

Last year, he was sentenced in absentia to eight and a half years in prison for publishing “false information” about the Russian military, and independent Russian media believe the authorities have filed a case against him for “treason.”