Ukrainian prosecutors have initiated a criminal investigation into the arrest of Mejlis leader Ilmi Umerov in Russian-occupied Crimea.
Kiev accuses Russian self-proclaimed authorities on the peninsula of violating human rights of Ukrainian citizens.
"It is established that Russian FSB security service searched the home of Ilmi Umerov, the Deputy Chairman of Crimean Tatars Mejlis, and arrested him, in violation of the Ukraine's Constitution", the Prosecutor's Office report.
Ukrainian officials say, the so-called Crimean government is suspected of committing several crimes, particularly, kidnaping and property rights violation.
Deputy Chairman of Crimean Tatars Mejlis Ilmi Umerov was arrested by Russian FSB security service on May 12.
He was forcibly taken from his home and brought to the local FSB office in Simferopol.
Umerov was accused of "extremist activity, aimed to undermine Russian territorial integrity".
Later he was notified he was prohibited from leaving Crimea.
This arrest followed a long streak of similar detentions of Crimean Tatars.
Ukraine and E.U. have repeatedly called on Russia to stop violating the human rights of local citizens.