The deputy police chief of Baghdad and his son, also a police officer, were assassinated Monday.
The Iraqi Interior Ministry says Brig. Amer Ali Nayef and his son, Lt. Khalid Amer, were gunned down in Baghdad's south Dora district while traveling in a car on their way to work.
The killings were the latest in a series of assassinations of ranking Iraqi security force officials on the eve of a landmark Jan. 30 election that insurgents are trying to disrupt.
Last Tuesday, gunmen shot dead the governor of Baghdad, Ali al-Haidari, and six of his bodyguards.
Only a few minutes after the assassinations, a suicide car bomb exploded inside the courtyard of a police station in southern Baghdad Monday, killing at least four policemen and injuring 10 others.
The explosion took place at 8 a.m. in the Zafarniyah district, just as police at the station were in the process of changing shifts.
In other recent developments:
Hours before Sunday's roadside bomb attack on U.S. troops, the U.S. acknowledged dropping a 500-pound bomb on the wrong house during a search for terror suspects outside the northern city of Mosul. The military said in a statement that five people were killed.
The house's owner, Ali Yousef, said 14 people died when the bomb hit at about 2 a.m. Saturday in Aitha, a town 30 miles south of Mosul. An Associated Press photographer at the scene said the dead included seven children and seven adults. The discrepancy between the death counts could not be reconciled.
Such attacks are exactly what the United States does not want prior to national elections scheduled for Jan. 30.
Sunday, Iraq's most influential Sunni group said it will abandon its call for a boycott of the elections if the United States gives a timetable for withdrawing multinational forces.
The first democratic vote in Iraq since the country was formed in 1932 is certain to see the Sunnis lose their dominance to the Shiites, who comprise 60 percent of Iraq's 26 million people. Sunni leaders have urged a postponement of the vote, largely because areas of Iraq where they dominate are too restive for preparations to begin.
In what appeared to be another effort to persuade Sunni Muslims to participate in the vote, interim Prime Minister Ayad Allawi met Saturday with 116 tribal leaders, clerics and political personalities from the restive provinces of Anbar, Salahuddine and Nineva.
According to an Allawi spokesman, leaders at the conference expressed their support for "the democratic process in Iraq and cooperation with the government to stand against violence and terrorism."