Amid the continuing violence, the United Nations announced it was cutting its staff in Baghdad and Iraqis prepared to bury an assassinated member of Iraq's Governing Council.
The blast occurred about 9 p.m. Thursday at a market in Baqouba, about 30 miles north of Baghdad. Nine civilians died and another 18 were wounded, the Army said. Troops of the U.S. 4th Infantry Division rushed to the scene to help.
In Baghdad, the U.S. military said one soldier from the 173rd Airborne Brigade was killed and two others were wounded during an ambush in northern Iraq. The incident occurred about 11 p.m. Thursday when a rocket-propelled grenade was fired at their vehicle. The names of the victims were withheld pending notification of kin.
The death raised to 86 the number of U.S. soldiers killed by hostile fire since May 1, when President Bush declared an end to major combat in Iraq.
Also Friday, the military announced that a soldier from the 4th Infantry Division died and another was injured in a fire Thursday night in an abandoned building in the Tikrit area. No further details were released.
In other developments:
Meanwhile, Iraqi leaders prepared to bury Aquila al-Hashimi, one of three women on the 25-member Governing Council, who died Thursday of wounds suffered in an ambush near her home on Sept. 20. A convoy carrying al-Hashimi's body left the capital Friday for the funeral in Najaf, a Shiite holy city 110 miles to the south.
The current council president, Ahmad Chalabi, blamed her death on Saddam loyalists.
The commander of U.S. forces in Iraq, Lt. Gen. Ricardo Sanchez, has warned he would use whatever force necessary to defeat those who attack American soldiers.
The inability of the U.S.-led coalition to stop the violence was behind the decision Thursday by U.N. Secretary-General Kofi Annan to order a further reduction of U.N. international staff in Iraq. Annan's order came days after the second bombing outside U.N. headquarters in Baghdad on Monday killed an Iraqi policeman and injured 19 others.
The first bombing, on Aug. 19, killed 22 people at the Baghdad headquarters. At that time, about 300 international staff were in Baghdad and another 300 elsewhere in Iraq, and Annan ordered the number reduced to 42 in Baghdad and 44 in the north.
U.N. spokesman Fred Eckhard said he did not know how many of the 86 remaining international staffers would leave for Amman, Jordan, under the latest order. They are to depart within the next two days.
"This is not an evacuation, just a further downsizing and the security situation in the country remains under constant review," Eckhard said.
The new cuts were announced as the Security Council debates a new resolution the United States hopes will bring new troops and money to Iraq. Opponents of the U.S.-led war in Iraq — including France, Germany and Russia — are calling for the United Nations to take over the political transition and are demanding a speedier timetable for the handover of power than the United States has proposed.
President Bush is struggling to win international support for a U.N. resolution designed to bring fresh peacekeeping troops and financial support.
Powell claimed some success Thursday in forging a consensus at the United Nations on nation-building in Iraq. "We are seeing some convergence of views," he said after a meeting of the five permanent members of the Security Council.