Six policemen were killed when their western Baghdad station was hit with mortar and gunfire Thursday, while the U.S. military said an American soldier was killed by a roadside bomb in the capital.

In other scattered violence around Baghdad, four civilians were killed and five wounded in a mortar attack on a residential area in the Dora neighborhood in the city's south, while two more civilians and six more injured when a parked car bomb exploded in the northeast, police said.

The U.S. soldier was killed when the bomb exploded next to his vehicle in northern Baghdad on Wednesday, the military said in a statement. Further information is being withheld pending notification of next of kin.

CountryWatch: Iraq

A joint American and Iraqi patrol clashed with forces loyal to radical Shiite cleric Muqtada al-Sadr in Diwaniyah, 80 miles south of Baghdad, in a raid to arrest a Mahdi Army leader, police said.

Two Iraqi soldiers were wounded and four injured, said police Capt. Abbas al-Bayati. An Iraqi armored personnel vehicle and a U.S. Humvee were damaged, but there were no immediate reports of American casualties, al-Bayati said.

Al-Bayati said he was still trying to confirm whether there were any Mahdi Army dead or wounded.

In the attack on the Baghdad police station in the Khadra neighborhood, assailants first fired a mortar at the building then drove up in four cars and opened fire with machine guns, said police 1st Lt. Maitham Abdel-Razaq.

In addition to the six policemen killed, one more was injured, he said.

Another policeman was killed in the northern city of Mosul in a morning drive-by shooting, police said.

One more policeman was killed and another wounded when a police car was fired upon by unknown assailants in downtown Baqouba, 35 miles northeast of Baghdad, police said.

Meanwhile, two people were killed and another nine injured when a car bomb exploded near an electricity office in Baghdad, police said.

The bomb placed in a parked car exploded just before 9 a.m. in the Hurriya neighborhood of the capital, police 1st Lt. Thaer Mahmoud said.

In the northeastern Diyala province, a convoy was hit by a roadside bomb attack, injuring the governor's brother and three guards, police said. The governor was not in the convoy.

And in downtown Fallujah, 40 miles west of Baghdad, parts of two mutilated bodies were found.

One was decapitated with its, hands and legs chopped off but could still be identified by family members, said Police Lt. Mohammed Ismail said, without identifying the victim.

A severed head belonging to Ahmed Kamel, also known as Munem Abu Shaiba was found the previous day, Ismail said. Kamel was wanted by American forces for suspected insurgent activity.

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