Russian opposition politician Aleksei Navalny says a member of his Anti-Corruption Foundation (FBK) has been detained on a charge of inciting extremism.
According to a tweet by Navalny on January 15, Pavel Zelensky was detained over a tweet he sent last year following the self-immolation of journalist Irina Slavina in the city of Nizhny Novgorod.
In his tweet on October 2, Zelensky condemned the Russian authorities, saying they were responsible for the journalist's death.
Slavina died after setting herself on fire in front of Nizhny Novgorod's city police department on October 2 following a police raid on her apartment in an apparent search for evidence linking her to an opposition group.
Before setting herself on fire, Slavina posted a statement on Facebook saying, "Blame the Russian Federation for my death."
Slavina's self-immolation caused a public outcry, with many people demanding justice for the journalist.
The Commission on Freedom of Speech and the Protection of Journalists and the Commission on Civil Rights at the presidential Council on Human Rights have called on Russia's Investigative Committee to thoroughly probe the circumstances surrounding Slavina's suicide.
Last year, the Investigative Committee twice refused to launch an investigation into the tragedy, saying there was "no evidence" to prove that Slavina's death was a crime.
On January 12, the lawyer for Slavina's family, Aleksandr Karavayev, said that the Investigative Committee had resumed a preliminary investigation into the journalist's death.