Russian officials said that two police officers were killed and at least 15 others were injured in a special operation against suspected militants in Chechnya's Shatoi district.
It was not immediately clear whether any of the gunmen were killed or injured during the June 29 operation.
Police said the mountainous forested area where the suspected militants were hiding has been cordoned off.
Russia waged two wars in Chechnya in the 1990s but the region has been been relatively peaceful in recent years as insurgents have turned their focus to the nearby regions of Daghestan and Ingushetia.
Based on reporting by Interfax and RIA Novosti