Daghestan's Interior Ministry says one policeman was killed and two people were injured in a drive-by shooting in the republic's capital Makhachkala on July 12.
The ministry said unidentified attackers opened fire on police at a checkpoint.
Two policemen were injured, one later died of his wounds in the hospital.
The driver of a vehicle police had stopped at the checkpoint was also injured.
The attack comes after a district court judge was shot dead in his car and bomb blasts injured two policemen and also derailed a cargo train over the weekend in the restive North Caucasus republic.
Russia is struggling to quash an Islamic insurgency in the North Caucasus, which also includes Chechnya and Ingushetia.
compiled from agency reports
Related
Editors' Picks
RFE/RL has been declared an "undesirable organization" by the Russian government.
If you are in Russia or the Russia-controlled parts of Ukraine and hold a Russian passport or are a stateless person residing permanently in Russia or the Russia-controlled parts of Ukraine, please note that you could face fines or imprisonment for sharing, liking, commenting on, or saving our content, or for contacting us.
To find out more, click here.