Armed men have killed at least eleven people and wounded more than 20 others in separate attacks in Iraq.

The deadliest attack on Sunday was in Kazimiyah district in northern Baghdad, where fighters in a speeding car went on shooting spree that killed three civilians and wounding another, two police officers said.

In the northern city of Mosul, a car bomb went off at a house early in the morning while a joint army-police unit was conducting door-to-door searches.

The blast killed three policemen and one soldier, a provincial police officer said. At least 20 people, including four civilians, were wounded.

Also in Mosul, police said fighters gunned down a policeman in his car in the city centre. Authorities also found a body floating in the Tigris river, shot at close range with hands bound behind the back. Mosul, about 360km northwest of Baghdad, is a former stronghold of Sunni fighters.

In Iraq's western province of Anbar, the birthplace of the Sunni insurgency led by al-Qaeda in Iraq, three soldiers were killed and five wounded in two separate attacks by roadside bombs on their patrols, police and army officers said.

Two medical officials confirmed the casualty figures.

All officials spoke anonymously as they were not authorised to release information.

Attacks have decreased sharply in Iraq since the height of insurgency, but recent spikes in attacks amid months-long Sunni protests against the Shia-led government have raised fears that sectarian killings could gain momentum across the country.

Source: Agencies