Update: The St. Petersburg city court has ruled to uphold Shurshev’s and Pivovarov’s jail sentences on Thursday evening, Open Russia tweeted.

Two aides to opposition leader Alexei Navalny and exiled former oil tycoon Mikhail Khodorkovsky have been jailed for 10 days following May Day protests that ended in mass arrests on Wednesday.

The violent detention of Alexander Shurshev, who heads Navalny’s St. Petersburg office, and the nonviolent detention of Andrei Pivovarov, who chairs Khodorkovsky’s Open Russia pro-democracy group, were caught on camera during the marches. They were among 68 people taken into custody in St. Petersburg that day, while at least 124 were detained overall across Russia.

Shurshev and Pivovarov each received jail sentences of 10 days, St. Petersburg activists said early Thursday morning.

The two were found guilty of organizing an unsanctioned rally “within a sanctioned demonstration,” the police-monitoring OVD-Info website reported.

Police brutally detained several people, dragging them into police vans, according to Reuters witnesses. Some protesters carried banners saying “For fair elections” and “Petersburg against United Russia,” a reference to Russia‘s ruling party which supports President Vladimir Putin.

The protests took place at a time when Putin’s rating has fallen to around 60 percent from a high of some 90 percent. That, say pollsters, is partly because the government has announced unpopular moves to raise the retirement age and hike value added tax after five years of falling real incomes.

Reuters contributed reporting to this article.