Russian forces have reportedly used helicopters and artillery fire to pursue a group of 15 suspected terrorists in the North Caucasus.
Russian news agencies are quoting security sources as saying that there were no immediate reports on casualties.
The militant group was surrounded in a wooded area in Daghestan after firing at a military helicopter and forcing it to make an emergency landing.
Authorities say no one was injured in that attack.
On March 6, a female suicide bomber killed five police officers during an attack on a police station in Daghestan.
Armed clashes between Islamist insurgents and Russian forces are frequent in the region.
With dpa and ITAR-TASS reporting