Russian soldiers and police continue their search in the southern republic of Dagestan for Chechen fighters who killed nine border guards earlier this week.

Hundreds of troops and police are traveling through the mountains of western Dagestan in search of the militants, who also took 11 people hostage in two Dagestan villages along the Dagestan-Georgia border. The hostages were later released.

Tuesday, Russian authorities reported killing at least six Chechen fighters by helicopter strike near the (Dagestan-Georgia) border.

Some officials say the Chechen attackers entered Dagestan from Chechnya, but others insist they crossed the international border from Georgia.

Meanwhile, a Russian soldier was killed and another seriously wounded late Tuesday in southwest Dagestan. Russia says it is not clear if the Chechen militants are behind the shooting.

Chechen separatist incursions into western Dagestan in 1999 in part triggered Russian President Vladimir Putin's current military campaign in Chechnya.