According to the source, the day before unknown masked individuals shot the policeman dead from submachine-guns at the Borozdinovskaya village.
"A Kalashnikov submachine-gun with rounds was stolen from the deceased. Investigation has been launched," the agency's interlocutor said.
On the same day two other policemen, a captain and an ensign of the Lipetsk special police force from the Central federal district, were killed in an explosion of a heavy armored truck. Two other policemen were severely wounded.
Also on Monday a security service agent of the head of the town of Argun was killed in an explosion of his car, the source reported.
According to him, a grenade exploded in the agent's Lada car 60 m from the townhall yesterday evening.
"The owner of the car died, the car burned down. Investigation is underway," he added.