The source said the assailants opened fire on an observation post in the village of Gudben, where four police volunteers were on duty.
This is the second incident in the republic involving militants over the past 24 hours. On Thursday police surrounded a building in the town of Khasavyurt killing five militants as part of a special operation.
Unarmed police volunteers are employed extensively throughout the North Caucasus to support law enforcement agencies in maintaining law and order in the region.
Daghestan borders Chechnya, which was a scene of violent battles between Islamic separatists and federal troops in the 1990s and early 2000s as the Kremlin tried to regain control over the republic. Although the active phase of all-out counter-terrorist operations in Chechnya ended years ago, sporadic clashes with small militant groups in this and neighboring republics are not uncommon.
