Russia's Federal Security Service (FSB) said on Wednesday it had detained 19 suspected Islamist militants planning attacks in the North Caucasus.
The FSB said it had seized a suicide belt, homemade bombs and automatic weapons from the suspects this month.
The 19 detainees, suspected members of the Takfir wal-Hijra Islamist group, were spread across the Rostov, Krasnodar and Karachay-Cherkessia regions, as well as Crimea, the peninsula Moscow annexed from Ukraine in 2014.
Footage from the detentions published by Russian news agency RIA showed FSB operatives scaling an apartment building and entering through a window to detain a suspect.
Russia has repeatedly been targeted by Islamist militant groups, including in an attack on a train carriage in a St Petersburg metro tunnel in 2017.
In recent years, some parts of the North Caucasus have been plagued with militant attacks on security officials.