Unidentified attackers fired automatic weapons at a police car Tuesday in southern Russia's Ingushetia republic, killing three police officers, an Ingush law enforcement official said.

"The unidentified men were moving in two vehicles. The firing left three policemen dead, and one more was wounded," the official told the Interfax news agency.

Police have launched a search operation for the assailants, the official said.

In a separate attack earlier, an officer of the Russian Federal Security Service's Chechnya department was killed in Ingushetia.

The Ingush Interior Ministry said two unidentified assailants, masked and clad in camouflage uniforms, broke into the house of the security officer at midnight and shot him to death with automatic weapons.

Ingushetia borders war-torn Chechnya, a volatile region in Russia's North Caucasus that is plagued by frequent attacks blamed on separatist rebels there that targeted security forces as well as civilians.

Source: Xinhua