Police in Moscow detained Russian opposition politician Aleksei Navalny's election campaign chief, Leonid Volkov, on October 5 just hours after he was released, his lawyer says.
Meanwhile, a coordinator of Navalny’s presidential campaign in Rostov-on-Don has also been detained.
Volkov's lawyer, Ivan Zhdanov, wrote on Twitter that his client was detained again despite a Moscow court decision earlier on October 5 to canceled a lower court's decision to sentence his client to 20 days in prison.
It was not immediately clear why Volkov was detained again.
Zhdanov earlier said that the case against Volkov was sent for reinvestigation to Nizhny Novgorod, where he was initially arrested.
Navalny and Volkov were found guilty of calling for an unsanctioned rally in the western Russian city of Nizhny Novgorod and sentenced to 20 days in jail each by different courts in Moscow on October 2.
Navalny is campaigning for next year's presidential election on March 18.
In Rostov-on-Don, campaigners in that southern city said that Anastasia Deineka was detained on October 5 by officers of the local branch of the Antiextremism Center, a federal agency under Russia's Interior Ministry.
It is not immediately clear why Deineka was detained.
Activists said the detention might be an attempt by local authorities to prevent Navalny's supporters from holding an unsanctioned rally planned for later this week.
Deineka is one of many Navalny staffers or supporters to face prosecution as the anticorruption crusader mounts an effort to run in Russia's March 2018 presidential election.
His supporters plan to organize mass rallies across Russia on October 7, despite the Kremlin's warning that organizers of unsanctioned public gatherings will be prosecuted.