Six suspected rebels, including three women, have been killed in a security sweep in Russia's restive North Caucasus, the interior ministry said on Friday. The ministry's spokesman in the Caspian Sea province of Dagestan, Vyacheslav Gasanov, said special forces cornered the suspects in a private house in the regional capital, Makhachkala. He said they refused to surrender and five of them were killed in a skirmish on Friday. Gasanov said that another one approached police and blew herself up with a hand grenade. He said no police officers were hurt. Dagestan and other Caucasus provinces have been rocked by an Islamic insurgency that has spread across the region following two separatist wars in Chechnya. Dagestan has become the main epicenter of violence with daily attacks on police and other authorities.