MOSCOW - Russia's Federal Security Service (FSB) has prevented a planned terror attack in the country's Rostov region by a cell of the Islamic State (IS) terrorist group, the FSB said Tuesday.

During a joint combat operation, security officers and the police detained three members of the cell who were under the order of IS emissaries based in Syria and planned to carry out massive terror attacks with firearms and explosive devices in the Rostov region in the Southern Federal District, according to an FSB statement.

The cell's leader detonated an explosive device and died while rendering armed resistance, it added.

Firearms including an AK-47 rifle, hand grenades, ammunition for improvised explosive devices, as well as means of communication and electronic storage devices containing propaganda materials of IS terrorist activities were seized at the scene of the incident, the statement said.

Investigations and necessary operational measures are underway, the FSB said.