Iraqi security officials say six policemen and two civilians were killed in two separate attacks in Baghdad Thursday.
The officials say gunmen attacked a police station in the city's upscale Mansur district, killing six officers and wounding another.
And, two people died and at least eight others were wounded in a car bomb blast in a Shi'ite neighborhood market in northeastern Baghdad.
Separately, a spokesman for radical Shi'ite cleric Moqtada al-Sadr, said Iraqi security forces arrested one of the cleric's top aides and three other members of his organization during an overnight raid in the holy city of Najaf.
In another development, Iraqi forces formally took over security responsibility of the southern Dhi Qar province from the Italian contingent of the Multi-National Forces.
Italian Defense Minister Arturo Parisi joined Iraqi Prime Minister Nouri al-Maliki in the handover ceremony at the regional capital of Nasiriyah.
The relatively peaceful Dhi Qar province is the second Iraq province under local control. Two months ago, Japanese troops pulled out of the mainly desert Muthanna province, handing it over to Iraqi forces.
The handover took place amid a recent spike in sectarian violence and insurgent attacks in the country.
A United Nations report released Wednesday said nearly 66-hundred Iraqis were killed in July and August, with more than half of them killed in July. The figure is much higher than the previous two months.
Major General William Caldwell, a top U.S. commander in Iraq, says he expects attacks to increase further during the Islamic holy month of Ramadan, which is expected to begin Saturday.
Some information for this report was provided by AFP, AP and Reuters.