A suicide car bomber killed at least eight people in an attack on a police checkpoint in Baghdad on Friday, after a night of U.S. air strikes around the city of Falluja that killed scores. A government spokesman said the bomb had detonated beside a line of police vehicles set up to seal off routes to nearby Haifa Street, where U.S. troops were pressing on with the battles they have been fighting all week to dislodge insurgents. The Interior Ministry said five police had been killed and the Health Ministry said at least three civilians were also dead, and the toll could rise. Earlier, a government spokesman had put the death toll at 13. A large crater was gouged into the road and several police cars were set ablaze, sending thick smoke into the sky. On Tuesday, a suicide car bomb attack on a police station killed 47 people, the deadliest attack in Baghdad in six months. The U.S. military is fighting to regain control of guerrilla strongholds and restore security so that elections can be held in January as planned. But there are growing doubts over the polls and U.S. Secretary of State Colin Powell conceded they could not be held under current security conditions. --More 2349 Local Time 2049 GMT