Head of the Central Election Commission of Kurultai of the Crimean Tatar people Zair Smedliaev wrote on Facebook, Censor.NET reports.
"Nikolay Polozov was detained by FSB officers and taken to the agency's directorate for questioning," Smedliaev wrote.
Meanwhile, Russian journalist Anton Naumlyuk reported that the FSB members detained Polozov in Simferopol to interview him as a witness in the case of Ilmi Umerov.
"He just flew in today after delivering a speech in PACE and was detained immediately upon arrival to the hotel at Sierova Street," the journalist wrote.
Polozov earlier said that FSB investigators threatened to forcibly bring him to the Crimean Directorate of the FSB for an interview.
As reported, Polozov is currently representing Crimean Tatars Ilmi Umerov and Ahtem Chiygoz in the Russian court.