Seven militants are killed in Dagestan 's capital , Makhachkala , Russian state media say . Investigators say the military operation was an attack Friday , state media say . The latest incident follows years of unrest linked to an Islamist insurgency in Dagestan and the North Caucasus region . Security has been stepped up in Russia ahead of the Winter Olympics next year . Dagestan is about a 12-hour drive from Sochi , host city for the Games .
Seven militants are killed in Dagestan 's capital , Makhachkala , Russian state media say . Investigators say the military operation was an attack Friday , state media say . Security has been stepped up in Russia ahead of the Winter Olympics next year . Dagestan is about a 12-hour drive from Sochi , host city for the Games .