Three lawyers who once represented the late Russian opposition leader Alexei Navalny were convicted by a court Friday as part of the Kremlin’s crackdown on dissent that has reached levels unseen since Soviet times.

Three lawyers for Alexey Navalny, the Kremlin critic who died last year in an Arctic prison, have been found guilty by a Russian court of belonging to an extremist group and jailed for several years.

The trio were arrested as authorities intensified pressure on the jailed Kremlin critic, who died last February.