MOSCOW, December 24. /TASS/. Over 640 people from the Russian North Caucasus republic of Dagestan are fighting among the militants of the Islamic State (IS) terrorist organization, Ramazan Abdulatipov, the leader of the republic, said in an interview with Vedomosti daily.

He said it was one of the main problems in Dagestan nowadays and the authorities do everything possible to prevent people from leaving the republic and joining IS.

"Anti-terrorism commissions work in every district," he said. "Each mosque, each local administration were ordered to hold talks and keep contact with all those, who are in the crisis zone, who had any contacts with militants, who is unsettled or dissatisfied with something. Work must be conducted with everyone."

The Dagestani leader also said that at a session of the Antiterrorism Committee he proposed confiscating passports from people, who leave to fight among terrorists in order to make it impossible for them to move across the countries.

"We must resort to crucial measures in the fight against such people," Abdulatipov added.