A man detonated explosives packed into his car as he approached a police checkpoint north of the western Iraqi city of Falluja Sunday, killing a policeman, authorities said.

Health officials said five policemen and three civilian bystanders were injured.

Police said many military vehicles were been badly burned by the explosion.

Falluja, some 60 km to the west of Baghdad in Iraq's Sunni Muslim heartland, was formerly the site of some of the worst fighting between insurgents and US and Iraqi forces, but has been quieter since US and Iraqi forces enticed many to switch sides and join government-allied Sahwa, or 'Awakening' militias.

Police added that they had foiled an attempted truck bombing in al-Qaim, on Iraq's western frontier, Sunday, shooting one man in the truck and arresting a second man.