BAGHDAD — A suicide bomber detonated explosives Sunday amid U.S. and Iraqi troops who were investigating an earlier attack. Iraqi police said nearly 20 people died, and the U.S. military said they included one American soldier.
It was the day's worst attack among several that occurred across Iraq, including one at a crowded bus depot in Baghdad that left four people dead.
The bloodshed came as U.S. and Iraqi negotiators tried to finalize details of an accord laying out the future for American troops in Iraq. The pact is needed because the United Nations mandate for the U.S. presence in Iraq expires at the end of the year.
In comments on Iraq's Al Hurra television, Foreign Minister Hoshyar Zebari said the pact "is about to be finished" and probably would be presented to parliament when lawmakers return from their summer break next month.
Zebari said Iraq was pressing for a clear timetable for the withdrawal of U.S. troops, but he did not give dates. Prime Minister Nouri Maliki has said he hopes American combat troops can be gone by the end of 2010, leaving behind only advisors and support troops.
Sunday's attacks showed the challenges still facing American forces in Iraq, who number about 140,000, and the Iraqi security forces who ultimately will have the task of protecting the country.
Police in the largely Sunni Arab town of Tarmiya, 25 miles north of Baghdad, said the attack there was two-pronged. First, a bomb was detonated inside a house belonging to a Shiite family. Witnesses and police said the bombers were a group of men disguised as members of the Awakening, the U.S.-allied movement of civilians who serve as a neighborhood security force. They entered the house ostensibly to search it, but planted bombs.
Khadim Hayali, who runs a food store nearby, said nobody noticed anything unusual. "The Awakening forces roam the area all the time," he said.
After the men left the house, a blast shook the street.
When Iraqi and U.S. forces arrived, the suicide bomber mingled with the crowd and detonated explosives.
"I amazingly survived," said Hayali, who had gone to the site. "I was running and kept touching my head, legs and arms to make sure I wasn't hurt, because I couldn't believe I wasn't hit."
Iraqi police said the dead included three Iraqi soldiers, eight civilians, and six Awakening members, along with two U.S. soldiers, but the U.S. military said in a statement that one American was killed and two were wounded. There was no explanation for the discrepancy.
The police initially said the bomber was a woman but later reported that there was no confirmation of that.
At least 4,138 American troops have been killed in Iraq since the start of the war in March 2003, according to the website icasualties.org.
In Baghdad, four people died when a bomb went off at a bus station in an eastern neighborhood, and two people died in a blast targeted at a convoy of police and military vehicles carrying cash to a downtown bank.
The money was not taken or damaged, police said.
In Khanaqin, a city near the Iranian border about 90 miles northeast of Baghdad, two people died when explosives hidden beneath livestock on a pickup truck exploded.
Special correspondents in Baghdad and Baqubah contributed to this report.