Several Crimean Tatars have been detained in Ukraine's occupied Crimea region after Russian-installed security forces searched their houses in several villages.
Crimean Tatar activists wrote on Facebook that at least five Crimean Tatar men, all of them practicing Muslims, were detained on October 12.
Video footage posted by the activists showed security officials searching the homes of several Crimean Tatar families in the unidentified villages.
Several videos showed crowds of Tatar villagers protested the searches -- confronting the security officials and chanting prayers in Arabic.
The authorities did not issue any official statement about the searches.
The RIA Novosti news agency reported that "several leaders of the banned Hizb ut-Tahrir Islamic group were detained in the result of searches conducted in several settlements on the peninsula."
In September, a court in southern Russia sentenced four Crimean Tatars to lengthy prison terms after finding them guilty of being members of Hizb ut-Tahrir.
Hizb ut-Tahrir is a London-based Sunni political organization. It seeks to unite all Muslim countries into an Islamic caliphate but says its methods for reaching that goal are peaceful.
Russia banned Hizb ut-Tahrir in 2003, designating it a "terrorist organization."
Russia has been heavily criticized by international rights groups and Western governments for its treatment of Crimea's indigenous Turkic-speaking people since Russia seized and illegally annexed the peninsula from Ukraine in March 2014.
Arrests, disappearances, and killings of Crimean Tatars have been reported.