Police patrol a checkpoint in Russia's Dagestan Province after a deadly suicide blast there on Thursday.<br/> <br />The explosion killed three police offers and wounded another six, ripping a 4-metre hole in the checkpoint headquarters.<br/> <br />The bomber detonated explosives in a car as police tried to stop the vehicle on its way through the checkpoint.<br/> <br />One person is still unaccounted for.<br/> <br />Tensions are high in Russia's predominately Muslim North Caucasus region, as Islamist insurgents wage daily violence in a fight to establish an Islamist state.<br/> <br />Dagestan has emerged as the epicentre of violence.<br/> <br />The suicide bombing follows a police raid on a forest hideout that killed five militants earlier this week in Dagestan.
