As the violence flared, Sunni Arab leaders opposed anyone linked with sectarian violence being given ministries in the next government.
There was no word, meanwhile, on the fate of American journalist Jill Carroll, kidnapped in Baghdad on Jan. 7 and last seen in a video released Jan. 17. Her kidnappers threatened to kill the 28-year-old if all Iraqi female prisoners were not released within 72 hours.
Deputy Justice Minister Busho Ibrahim Ali has said six of the nine women in U.S. military custody were expected to be freed this week, but the U.S. military has not confirmed any imminent releases. Ali has said their releases were tentatively planned before the kidnappers' ultimatum.
The Council on American-Islamic Relations, a U.S. Muslim advocacy group, is in Baghdad to press for Carroll's release.
More than 240 foreigners have been taken hostage, either by insurgents or gangs, since the 2003 U.S.-led invasion that toppled Saddam Hussein. At least 39 have been killed.
Insurgents fired rocket propelled grenades at the home of an Iraqi police officer in Balad Ruz, 45 miles northeast of Baghdad, said a spokesman for the Iraqi police Joint Coordination Center. The officer's children, ages 6 to 11, and their uncle were killed, the spokesman said on condition of anonymity due to fears of reprisal attacks. The officer was unharmed, but his wife was wounded.
In other developments:
Sunni leader Tariq al-Hashimi, meanwhile, warned that Sunni Arabs would reject the inclusion in Iraq's new government of any official involved in violence against Sunnis by Shiite-backed security forces.
The warning appeared directed at Interior Minister Bayan Jabr, whom Sunnis accuse of playing a leading role in directing Shiite forces with militia links to kill Sunni clerics and lay people.
Before joining the Cabinet in 2003, Jabr was a senior official in the Badr Brigade militia of Iraq's largest Shiite party, the Supreme Council of the Islamic Revolution in Iraq. He has denied involvement in killing Sunnis.
"We have red lines on some figures who harmed our people and we will not allow anyone who participated in human rights violation to take any ministerial posts," said al-Hashimi, head of the Iraqi Islamic Party and a partner in the prominent Sunni Arab Iraqi Accordance Front.
Al-Hashimi also said the next government must deal with Sunni Arab opposition to the new constitution, including provisions transforming Iraq into a federal state and banning key members of Saddam's Baath party from government jobs.
"The new government must promise not to hamper the expected changes on the constitution that divided the Iraqi people more than uniting them," he said.
But Iraq's most powerful Shiite politician, Abdul Aziz al-Hakim, has said that the Shiites would oppose major concessions on some key Sunni demands.
Al-Hashimi's comments come as Iraq's dominant Shiite leaders prepare for talks with Kurdish and Sunni politicians to form a national unity government, following Friday's release of results from Dec. 15 elections. The United States considers a unity government crucial to curbing the Sunni-led insurgency and paving the way for American forces to go home.
The major Shiite coalition, the United Iraqi Alliance, captured 128 of the 275 seats, not enough to rule without partners. Two Sunni coalitions won a total of 55 seats, far more than the 17 held by Sunnis in the outgoing parliament.
Sunni politicians said they would appeal results to a judicial commission, which has two weeks to rule on the challenges. The appeals are unlikely to affect the results but could delay the convening of parliament.