Two police officers were killed when unknown...

"Unknown people opened fire on a Lada Priora car with law enforcement officers inside in the Khasavyurt District. Two policemen were killed," a local police spokesman said.

An investigation is underway.

Russia"s mainly Muslim and ethnically diverse North Caucasus republics have been swept by an upsurge of violence recently, which has also swept neighboring regions, where hundreds of people have been killed in militant attacks and skirmishes between security forces and gunmen.

Moscow announced an end to its decade-long antiterrorism campaign against separatists in Chechnya in April 2009, but has since had to step up the fight against militants as skirmishes and attacks on police and other officials have continued.

MAKHACHKALA, February 14 (RIA Novosti)