MOSCOW - Two militants were killed in a special operation Sunday in Russia's North Caucasus republic of Dagestan, said local police.

The security sweep was carried out in the morning, when law enforcers blocked a group of militants in a private house in the village of Novosasitly in central Dagestan.

The local police said two militants and one police officer were killed during the fire exchange, while another officer was injured.

The law enforcers found a homemade explosive device, two Kalashnikovs and several grenades in the house, reported the Itar-Tass news agency.

The killed gunmen were members of an armed gang, which had engineered a major terror act in Makhachkala, the Dagestani capital, last summer, said a spokesman of the information center of the National Anti-Terror Committee.

Violence is common in Russia's North Caucasus, especially in republics of Chechnya, Dagestan and Ingushetia, with militants frequently mounting attacks against police officers and authorities.

In 2011, Russian security forces eliminated over 300 militants in the troubled North Caucasus republics.