BAGHDAD, Iraq - Five U.S. soldiers and four Iraqis were killed Saturday and dozens of people were injured in three bombings in the volatile region known as the Sunni Triangle that extends north and west of the capital.
In an apparent suicide attack, a car reportedly crashed into a checkpoint and exploded outside a U.S. military installation near the town of Khaldiya, about 45 miles west of Baghdad, killing three U.S. soldiers and wounding six.
Earlier in the day, a bomb exploded in a truck parked outside a courthouse and municipal center in the city of Samarra, about 60 miles northwest of Baghdad, killing four Iraqis and injuring more than 30 people, according to official reports.
A third blast in the city of Fallujah, 35 miles west of the capital, killed two U.S. soldiers when a bomb exploded as a military convoy was passing.
The bombs brought the U.S. military death toll in Iraq to 512.
The attacks came a day after a team of U.N. security experts arrived to study conditions in Iraq and assess the possibility of resuming U.N. activities. A senior Bush administration official, meanwhile, said at an international forum in Davos, Switzerland, that the United States was willing to commit resources to help alleviate U.N. security concerns.
Most U.N. operations in Iraq were shut down after a suicide bomber exploded a truck outside U.N. headquarters here in August, killing 22 people, including the senior U.N. representative, Sergio Vieira de Mello.
Senior U.N. officials have not yet decided whether to send a second team requested by American and Iraqi officials to assess the feasibility of holding direct national elections in the next several months, as key Shiite Muslim leaders have demanded.
Extremist groups have regularly detonated mines and explosives in attacks against military convoys in recent months, especially in the region of central Iraq that is a nucleus of Sunni Muslim opposition to the U.S. occupation.
Until recently, though, suicide bombings were relatively infrequent. Then last Sunday, a massive car bomb exploded outside the main gate to the central U.S. compound in Baghdad, killing 31 people and wounding 120 others. The blast appeared to be targeted at Iraqi workers who were streaming past the gate to report to U.S. facilities inside.
In the case of the Samarra bombing Saturday, Iraqi and U.S. officials said the attack was an attempt to derail local elections. The bomb exploded about 10 a.m., just before local representatives were scheduled to vote for members of a provincial council.
"I am sure the bomb was meant to prevent the vote," said Robert Silverman, a U.S. official working on governance issues in that region. The blast scattered glass and pieces of cars for some distance.
Spokesmen for the U.S. administration here said this past week that as Iraq moves closer to a transition of power from occupation to Iraqi authorities, extremists are targeting Iraqi leaders and officials in an attempt to undermine the political process.
"People are being attacked ... not because they are working with the coalition, but because they are working for the new Iraq," Brig. Gen. Mark Kimmitt, the chief U.S. military spokesman, said Saturday evening.
On Thursday, a bomb exploded in an Iraqi Communist Party office in Baghdad, killing two people. A sizable meeting there ended just before the blast.
The Khaldiya bombing, which occurred just after 4 p.m. Saturday, took place near a U.S. checkpoint at the Siddiqin Bridge. American military spokesmen said the attack also wounded at least eight Iraqi civilians. The injured were treated at various military bases and local hospitals.
No group has asserted responsibility for the recent attacks and officials have not reported identifying any suspects. U.S. officials have repeatedly attributed the attacks to either supporters of Saddam Hussein or Islamic extremist groups, which may include activists from outside Iraq.