Staff and supporters of presidential hopeful Alexei Navalny have been arrested and fined across Russia for organizing unauthorized demonstrations on Sunday that called for a “voters’ strike” of the March 2018 presidential elections.

On Jan. 31, Kira Yarmysh, the press secretary for Navalny’s Anti-Corruption Fund, was jailed for 5 days on charges of organizing a public event without a permit, and Ruslan Shaveddinov, his election campaign spokesman, was sentenced to 8 days, the Meduza news website reported. The two staffers were arrested upon arrival at Moscow airport on Tuesday.