Two policemen were killed and one injured when a police car was blown up on Saturday just outside the town of Malgobek in Russia's southern republic of Ingushetia, a local investigators said.

"A UAZ car with police in it near a gas station on the edge of Malgobek was blown up. Emergency services are on the way to the scene," he said.

The dead officers were provisionally named as Adam Kartoyev and Mikhail Tsokiyev.

A bomb went off along the route the car was taking, investigators said.

Ingushetia has been involved in a long-running battle between Islamist insurgents and federal security forces for control of the republic and the wider North Caucasus.