Bloody Sunday (Russian: Кровавое воскресенье) was an incident on January 22 [O.S. January 9] 1905 in St. Petersburg, Russia, where unarmed, peaceful demonstrators marching to present a petition to Tsar Nicholas II were gunned down by the Imperial Guard. The march was organized by Father Gapon, who had collaborated with Sergei Zubatov of the Okhrana, the Tsarist secret police, to create workers' organizations^[1] and thus considered by some to be its agent provocateur. Bloody Sunday was an event with grave consequences for the Tsarist regime, as the disregard for ordinary people shown by the massacre undermined support for the state.