Police officer Moussa Abdul Karim said the explosion in northern Baghdad's Shula neighborhood was followed by a gunfight between suspected insurgents and U.S. soldiers that lasted about 10 minutes before the militants fled.
Another car bomb exploded as an Iraqi patrol passed in Baghdad's Karradah neighborhood, killing one police officer and injuring three bystanders.
In the northern city of Kirkuk, gunmen killed two Iraqi soldiers.
(compiled from agency reports)