Two are dead after a suicide bomber blew up his car at a checkpoint in Russia's restive North Caucasus, killing himself and a police officer.

Another four were wounded in the blast before dawn on Tuesday.

The bombing happened along the border of Ingushetia province and North Ossetia.

Moscow has struggled to stamp out an Islamist insurgency in the North Caucasus region where violence is a daily phenomenon.

The conflict stems from two bloody wars Moscow fought with separatists in nearby Chechnya as well as rampant poverty, corruption and human rights abuses.