Suspected al-Qaida militants on Monday blew up the house of a policeman in a former stronghold of the Sunni insurgency west of Baghdad, killing him, his wife and 4-year-old daughter, hospital and police officials said.
Separate attacks in Baghdad, including one targeting police, killed five people and wounded 15.
Al-Qaida militants have been targeting policemen and members of anti-al-Qaida Sunni militias, shaking an increasingly fragile security situation in Iraq as politicians wrangle for months over forming a government. July was the deadliest month for Iraqis in two years, though violence remains down from 2008.
The policeman's house was blown up before dawn in the Karmah district outside the city of Fallujah while the family was sleeping, police and hospital officials said.
Seven other family members, including four of the policeman's sons, were wounded in the blast, the officials said, speaking on condition of anonymity because they were not authorized to talk to the press.
The police officials said they suspected al-Qaida militants were behind the attack.
Also on Monday, police officials said a roadside bomb apparently targeting a police patrol missed and killed three civilians traveling in a car and wounded eight bystanders in the western part of Baghdad.
Shortly after midnight, police and hospital officials said gunmen in a car opened fire at a cafe in Baghdad's Shiite district of Sadr City, killing two people and wounding seven.
Residents said the attack may have been the work of vigilantes angered by suspected drug use at the cafe.
All officials spoke on condition of anonymity because they were not authorized to speak to the media.
Violence has dramatically declined in Iraq since 2008, but attacks remain a daily occurrence, especially in Baghdad. Figures released by Iraqi authorities over the weekend showed that July was the deadliest month for Iraqis in two years, with 535 people killed compared to 563 in May 2008.
The figures, dismissed by the U.S. military as too high, deepened concerns over Iraq's precarious security even as a political deadlock persists nearly five months after a parliamentary election produced no clear winner and the United States continues to draw down on its forces.
All but 50,000 U.S. troops will be left in Iraq by the end of this month and the last American soldier will leave by the end of next year. There are an estimated 65,000 U.S. troops currently in Iraq.