Police in Russia say a warlord suspected to be behind multiple attacks in the North Caucasus and four of his accomplices have been killed in a police operation in Dagestan.

Police spokeswoman Fatina Ubaydatova said Sunday that the five were killed late Saturday on the outskirts of the regional capital, Makhachkala.

The regional office of the Russian Investigative Committee identified one of them as Rustam Aselderov, who was wanted for his suspected role in several attacks in Dagestan, including a bombing at a train station in southern Russia that killed 34 people.

Dagestan, a predominantly Muslim province on the western shore of the Caspian Sea, has become the epicenter of an Islamic insurgency following two separatist wars in neighboring Chechnya.