MAKHACHKALA, May 14 (RIA Novosti) - A militant leader was among four gunmen killed in a special operation in Russia's North Caucasus republic of Daghestan, a Federal Security Service (FSB) spokesman said on Thursday.

"The bodies of four militants have been found. One of them was identified as Arsen Asulbegov, the leader of the Khasavyurt militant group, who was wanted for attacks on police officers," the source said.

Up to 10 militants were discovered holed up in Daghestan's Khasavyurt District on Wednesday during the operation. A Federal Security Service officer also died during the subsequent fighting.

A large amount of weapons and ammunition was also discovered stored nearby.

"Security officers are continuing their search in the wooded area where the militants were hiding," the source added.

Militant attacks and clashes with federal forces are common in Russia's North Caucasus republics.