Colonel Akhmedudin Absaludinov, deputy head of the investigation and search division at the republican interior ministry's department for combating economic crimes, was shot dead in the center of Makhachkala early on Sunday when an unidentified person opened fire at him, the police source said.
The murder of Absaludinov is linked to his professional activity. Absaludinov had led the fight against corruption in the republic for a long time, the prosecutor's office of Daghestan said.
Efforts are under way to find the attacker.
In a similar attack, Anatoly Kyarov, who led the fight against organized crime in the North Caucasus Republic of Kabardino-Balkaria, was killed along with another police officer when armed gunmen attacked the car, in which they were travelling, in the republic's capital of Nalchik on January 13.