The assault late Wednesday occurred near the town of Alpatovo in relatively calm northern Chechnya, the region's Interior Ministry said. Two members of a police unit from Siberia serving in Chechnya were killed, and the attackers fled, it said.
In other violence Wednesday, the explosion of what was likely a homemade bomb ruptured a natural-gas pipeline in the North Caucasus republic of Kabardino-Balkaria, cutting supplies to about 200 homes, according to a spokesman for the Emergency Situations Ministry's southern Russia branch, Sergei Kozhemyaka. He said supplies were expected to be restored late Thursday.
In Chechnya's capital Grozny, meanwhile, an Interior Ministry serviceman fatally shot a local man in the head during an argument in a gas-station parking lot, the Chechen Interior Ministry said. Authorities were searching for the serviceman, who fled the scene, it said.
Residents and human rights organizations accuse government forces of abuses of civilians across the North Caucasus, a string of internal republics that are home to mostly Muslim ethnic groups and have been plagued by various levels of violence in recent years. Chechnya has been devastated by two wars since 1994 pitting government forces against separatist rebels.
Violence and tension have increased in recent months in Ingushetia, a small republic just west of Chechnya where attacks on police and other law enforcement officials are common.
On Friday, a car-bomb blast killed four policemen in Ingushetia's main city, Nazran, and gunmen fatally shot three members of a Russian-speaking schoolteacher's family at their home in the town of Karabulak.
The regional branch of the Federal Security Service said Thursday that it was searching homes and vehicles in Karabulak, looking for a suspected militant leader, but later announced that the search was over and that the suspect had not been found.
The discovery of the submarine has unveiled a few "inconsistencies." For example, how can one explain the fact that the sub was found where it needed to be searched for from the start?
The TurkStream, which runs along the bottom of the Black Sea from Russia's Anapa to Turkey, will consist of two lines, each with a capacity of 15.75 billion cubic meters of gas a year