SIMFEROPOL, Ukraine -- Russian authorities have detained several Crimean Tatar activists after their homes were searched in Ukraine's Russian-controlled Crimea region.

The Crimean Solidarity group told RFE/RL on February 17 that the searches were conducted at the homes of Abdulbori Makhamadaminov, Azamat Eyupov, Timur Yalkabov, Ernest Ibragimov, Oleh Fyodorov, Lenur Seydametov, and Yashar Shikhametov in different towns and cities across Crimea.

The official reason for the searches remains unclear.

Ukrainian Ombudswoman Lyudmyla Denisova said in a statement that all of the men were taken to the FSB's directorate in Crimea after the searches.

"Such actions by so-called law enforcement violated the presumption of innocence, and rights of freedom, personal security, legal assistance, as the searches were conducted without court decisions, with no lawyers present, and without handing out of any procedural documents," Denisova said, adding that the detained Crimean Tatars may face long-term arrests.

Since Russia seized Crimea in 2014, the Russian authorities have prosecuted dozens of Crimean Tatars for allegedly belonging to Hizb ut-Tahrir, an Islamic group that is banned in Russia but not in Ukraine.

Moscow's takeover of the peninsula was vocally opposed by many Crimean Tatars, who are a sizable minority in the region.

Exiled from their homeland to Central Asia by the Soviet authorities under dictator Josef Stalin during World War II, many Crimean Tatars are very wary of Russia and Moscow's rule.

Rights groups and Western governments have denounced what they describe as a campaign of repression by the Russian-imposed authorities in Crimea, who target members of the Turkic-speaking Crimean Tatar community and others who have spoken out against Moscow's takeover of the peninsula.

In its annual report on religious freedom worldwide, released in April 2020, the U.S. Commission on International Religious Freedom said that "[in] Russian-occupied Crimea, the Russian authorities continued to kidnap, torture, and imprison Crimean Tatar Muslims at will."

Russia took control of Crimea from Ukraine in March 2014 after sending in troops, seizing key facilities, and staging a referendum dismissed as illegal by at least 100 countries.

Moscow also backs separatists in a war against government forces that has killed more than 13,200 people in eastern Ukraine since April 2014.