Abu Hamza al-Muhajer (file photo)

The Iraqi Defense Ministry says its forces have arrested the leader of the group al-Qaida in Iraq.

News reports quote a ministry spokesman saying that the man known as Abu Hamza al-Muhajir was captured in the northern city of Mosul.

In Baghdad on Thursday, a car bomb exploded in the Iraqi capital's Mansur district, killing seven people and wounding at least 19 others. Officials say three policemen were among those killed.

US soldier patrols in Baghdad's Sadr City

Also in the capital, at least one rocket landed in the center of the city, killing at least two people and wounding four others.

In the southern port city of Basra, the U.S. military says several rockets slammed into a coalition military base today, killing two civilian contractors and wounding eight people. The military says six militants were killed in a counter attack.

Earlier today, medical officials said seven people were killed in fresh clashes between Shi'ite fighters and U.S. forces in Baghdad's Shi'ite stronghold, Sadr City.

U.S. and Iraqi forces have fought fierce battles in Sadr City against Shi'ite militiamen loyal to radical cleric Moqtada al-Sadr for the past month.

Elsewhere in Iraq, a suicide bomber detonated his explosives as a police convoy passed through the town of Dhuluiyah, about 70 kilometers north of Baghdad. No one was killed, but at least three policemen were wounded.