Witnesses said at least 12 Iraqis were killed and 25 wounded in a car bombing in a busy marketplace in eastern Baghdad's predominantly Shiite district of Sadr City.
Security sources said gunmen shot dead five Iraqi civilians in three separate attacks in Baquba.
Gunmen opened fire on a blacksmith's workshop, killing three brothers, while another group of gunmen opened fire on an office building near the city centre, killing the office owner. Another civilian was shot dead at a travel station, also in the centre of Baquba.
Earlier today, Iraqi police reported that five members of the Kurdish security forces had been killed at a roadblock in Zanjar near the north-western city of Mosul.
Also in Mosul, unknown assailants killed a high-ranking police officer during a drive-by shooting. A further four Kurds were injured as the attacker blew up the car in which he was driving.
US soldiers killed
The US military also reported insurgents killed two more US soldiers.
The first was fatally wounded in a battle in in western Iraq's Al-Anbar province, coalition headquarters said.
The second was patrolling on foot south of Baghdad when an improvised bomb exploded and killed him.
The news came as US press reports said bomb attacks on US and Iraqi Army convoys reached record levels in July, a month after al-Zarqawi was killed.
More than 1,600 roadside bombs exploded in July, according to official army figures, and a further 1,000 were defused, compared to 1,500 bombs in January.
Peace deal struck
Security sources said the office of leading Shiite cleric Ayatollah Mahmoud al-Hassani had announced it had agreed to end armed clashes with Iraqi security forces in Karbala.
The agreement was reached following two days of clashes in Karbala in which six Iraqis, including two security force members,
were killed and 19 others, including eight soldiers, were injured.
More than 200 Iraqis were arrested, including supporters of Ayatollah al-Hassani, following clashes between the Ayatollah's loyalists and joint Iraqi police and armed forces in the city on Wednesday. The clashes had erupted following a travel dispute.
The agreement called for an end to the armed conflicts in the city, the handing over of the bodies of individuals killed in clashes to their family members, the release of 219 detainees arrested on Wednesday and for the office of the Ayatollah to remain under the supervision of security forces for 10 days.
In light of the agreement, the Governor of Karbala agreed to lift a curfew that was yesterday imposed on the city which is 100km south of Baghdad.