Four people died and 13 were wounded in a string of bomb blasts across Iraq on Tuesday.
A car bomb attack on a US patrol in the afternoon killed three civilians and injured eight others in the central Baghdad district of Mansour, a police source said.
Earlier, an Iraqi police colonel was killed and a deputy minister escaped unharmed in two bomb attacks that left five people wounded, officials said.
Police Colonel Adbulmajid Mohammed was killed by an explosive device planted under his car in the town of al-Zubair, near the oil-rich southern city of Basra, police said.
His driver, also a police officer, was rushed to hospital in a critical condition after the bomb detonated as they were driving to work.
In a second attack, a deputy minister, Ammar Aziz Mohammmed Ali, survived an assassination attempt in the Iraqi capital, the government said.
"A roadside bomb blew up as the deputy higher education minister's convoy was passing down al-Nidhal street in central Baghdad without hurting him," said a government statement.
Two civilians and two police officers were wounded in the incident, an interior ministry source said.
Attacks have fallen sharply across Iraq in recent months, according to US commanders who admit insurgents are still able to strike and that this is likely to increase before January 31 provincial elections.