A roadside bomb killed a U.S. soldier Wednesday in Baghdad, making May the deadliest month for the American military since September.
The attack occurred two days after a blast struck a U.S. convoy west of the capital, killing three Americans, including two civilians and one soldier.
The spike in deaths comes as U.S. forces face a June 30 deadline to pull back from urban areas as part of a U.S.-Iraqi security pact that took effect this year.
At least 20 American service members have died so far this month, compared with 25 in September, according to an Associated Press tally.
The 20 deaths include five service members killed in a May 11 shooting at a mental health clinic in Baghdad. Sgt. John M. Russell has been charged with murder in the case.
April had at least 19 American troop deaths, more than double the nine killed in March, which was the lowest since the war began in March 2003.
In Wednesday's incident, the soldier from the Multi-National Division — Baghdad died of injuries suffered when a bomb exploded near a patrol in a western section of the capital, the military said in a statement.
In all, at least 4,302 members of the U.S. military have died in the Iraq war, according to the AP count.
Four U.S. civilians also have been killed in Iraq since Friday.
They included a top reconstruction official who once headed the Illinois Commerce Commission and a Defense Department employee working for the U.S. Embassy who were killed in the roadside bombing on Monday on the eastern outskirts of the former insurgent stronghold of Fallujah.
A defense contractor also died in a rocket or mortar attack near the U.S. Embassy and another was found stabbed in his car on Friday.
Iraqis also have faced a resurgence of violence with a series of deadly attacks in recent months, illustrating the resilience of militants despite security gains.
In the latest attack, a car bomb exploded near a medical compound in Abu Ghraib west of Baghdad, killing at least two people and wounding 13, two police officials said, speaking on condition of anonymity because they were not authorized to release the information.
Belgium's Foreign Minister Karel de Gucht, meanwhile, called the plans for Iraqis to take over security of their cities after the Americans pull back an important step toward normalization.
De Gucht began a two-day visit to Iraq on Wednesday, the first such visit by a Belgian Cabinet minister since 1990.
Belgium opposed the U.S.-led invasion of 2003 that toppled Saddam Hussein, but like other European countries is reaching out to Iraq as a business and political partner now that security is improving.
Iraqi Foreign Minister Hoshyar Zebari welcomed assistance offered by Belgium, including debt reduction, financial aid for reconstruction projects and training for Iraqi judges, diplomats and Interior Ministry employees.
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