A U.S. air strike killed 8 Iraqi civilians, including two women, in the northern city of Baqouba on Wednesday, a day after U.S. tank fire killed five young Iraqi girls in the western Anbar province.
The U.S. army claimed that American soldiers clashing with Iraqi fighters in Baquoba called in air support that killed eight "al-Qaeda" rebels.
After the air strike, U.S. forces found the bodies of two Iraqi women, the military said in a statement.
But Iraqi police said all the dead were innocent civilians belonging to two families.
Witnesses said the victims included a man and his three sons, as well as another couple and their son and daughter.
Baqouba, 35 miles northeast of Baghdad, is the capital of Diyala province, which has witnessed some of the worst violence since the 2003 U.S.-led invasion of Iraq.
The Baqouba attack took place one day after U.S. occupation forces killed five young Iraqi girls, including at least one baby, when they raided a house in the western Anbar province.
The U.S. army claimed in a statement that fighters on the roof of a house fired on its troops, who responded with tank fire.
The youngest female casualty was six-months-old and the eldest was aged 10, reports say.
One man was also killed in the U.S. raid, which took place in the city of Ramadi, 115km west of Baghdad, the U.S. army said in a statement.
Another female was also wounded in the raid, but refused treatment by the Americans, the statement added.
The army claims that the killings took place after the soldiers discovered an improvised explosive device on the roadside in north-east Ramadi.
U.S. soldiers say as the bomb was being defused, two Iraqi men took up positions on the roof of a nearby house and began firing at them.
The Americans returned fire with machine guns and tank rounds, the military statement said.
After the firefight, the Americans discovered the six dead Iraqis in the house.
One of the Iraqi fighters may have been injured in the raid, the military statement said, adding that there were no U.S. casualties.
Hundreds of innocent Iraqi civilians have been killed in U.S. military operations since the invasion.
The volatile Anbar province has witnessed several attacks on Iraqi civilians since the war began. One unit of Marines is being investigated for the killing of 24 unarmed civilians in the western town of Haditha last year.
Bush meets Maliki in Amman
The deadly U.S. attacks came ahead of a scheduled meeting between President Bush and Prime Minister Nuri Kamal al-Maliki in the Jordanian capital, Amman.
The two leaders are expected to discuss ways to improve the security situation in Iraq, and transfer more responsibility to Iraq's security forces.
President Bush, who is facing growing political pressure over the lack of progress in Iraq, is expected to give public support to Maliki, but will pressure him privately to curb Iraq's growing violence, correspondents say.
In Iraq, the political bloc loyal to Shia cleric Moqtada al-Sadr decided to boycott the government and the parliament in protest at Maliki's meeting with Bush, which it criticized as a provocation to the Iraqi people and a violation of their constitutional rights.
The Amman summit comes one day after the 15-member United Nations Security Council extended the mandate of the multinational force in Iraq until the end of next year.
The move was requested by the Iraqi government, which said that UN troops were needed for another year while it built up its own security forces.
The mandate will be reviewed by 15 June, or earlier if Iraq requests.
About 160,000 foreign troops, the majority of them from the United States, operate in Iraq under the UN mandate.
Agencies