A Moscow court Monday sentenced seven opposition activists to up to four years in prison and an eighth to probation, officials said. The eight Russians were convicted Friday on charges of rioting and assaulting police officers, RIA Novosti reported. Charges stemmed from a May 2012 demonstration in Moscow's Bolotnaya Square during which protesters clashed with police. The rally was one of several large-scale protests organized against Russian President Vladimir Putin's return to the presidency. The seven male activists were sentenced to prison for different lengths of time. Sergei Krivov was sentenced to four years, Artyom Savyolov was sentenced to two years and seven months, Stepan Zimin and Aleksei Polikhovitch got 3 1/2 years, Andrei Barabanov was sentenced to three years and seven months and Yaroslav Belousov received a sentence of 2 1/2 years. The eighth activist, Alexandra Dukhanina, was given probation.