Investigators at the Crimean branch of Russia's Federal Security Service (FSB) have launched a criminal inquiry against Ilmi Umerov, deputy chairman of the Crimean Tatars' Mejlis, which is banned in Russia, on suspicion of inciting violation of Russia's territorial integrity, Crimean Prosecutor Natalia Poklonskaya said.

"While in Ukraine in March 2016, Umerov spoke live on ATR television, where he publicly called for the need to violate Russia's territorial integrity. Subsequently, Umerov's speeches were put out on the Internet," Poklonskaya wrote on her Facebook page.

The inquiry was opened under Article 280.1 part two of the Russian Criminal Code, she added.

"Currently, Umerov is being questioned at the FSB department office," she said.

A source familiar with the situation told Interfax that Umerov was released on travel restrictions, and investigators are going to search his house. This information was also confirmed by Mejlis members.

"The FSB investigator has given Ilmi Umerov a statement not to travel outside the city. FSB officers will conduct a search at his house. Following which, he will most likely be left at home," Mejlis' first deputy speaker Nariman Jelialov wrote on his Facebook page.

Meanwhile, Mejlis leader Refat Chubarov wrote on Facebook that his deputy was arrested by the FSB in Bakhchisarai, and then moved to Simferopol for indictment.

In April, the Crimean Supreme Court declared the Crimean Tatar Mejlis an extremist organization, and banned its activity in Russia. The decision prompted sharp criticism in Ukraine and the West.

Umerov had, for many years, led the Bakhchisarai district administration in Crimea.