Phone video footage has emerged showing the aftermath of a US attack in Afghanistan.
US forces in Afghanistan are to review an inquiry into an air raid last month after new video evidence emerged indicating scores of civilian deaths.
The US had earlier said that no more than seven civilians died in the attack on the western province of Herat.
However, the Afghan government and the UN said up to 90 people were killed, including many women and children.
The US-based Human Rights Watch (HRW) says such attacks are eroding support for the government and foreign forces.
HRW says civilians deaths from international air strikes nearly tripled between 2006 and 2007.
The US general in charge of Nato-led troops (Isaf) in Afghanistan said at the weekend that he was requesting the US military's Central Command to review the investigation into last month's air raid.
Gen McKiernan said Isaf realised there was "a large discrepancy between the number of civilian casualties reported by US and Afghan National Army soldiers, and local people".
The US and Nato need to dramatically improve their co-ordination with each other and with the government of Afghanistan
Rachel Reid Human Rights Watch
The US military subsequently said it would "appoint a senior US military officer to review the investigation into the combined Afghan National Army (ANA) and US forces operation".
A US military statement said: "This review will consider new information that has become available since the completion of the initial investigation."
Disturbing video footage - apparently of the aftermath of the raid - has been seen by top military figures and diplomats in Kabul.
The shaky footage - possibly shot with a mobile phone - shows some 40 dead bodies lined up under sheets and blankets inside a mosque.
The majority of the dead are children - babies and toddlers, some burned so badly they are barely recognisable.
The covers are removed for the camera one by one: a little girl of perhaps four with brown curly hair; a boy with his eyes still eerily open; another girl with huge injuries on the side of her head.
Villagers say up to 90 civilians died in last month's attack by US forces
Another boy has his hand up as if to protect his face which was crushed under the rubble.
Clearly heard on the tape is the crying of relatives and the survivors of the bombing raid.
US forces had originally said seven civilians were killed in a "successful" US raid targeting a Taleban commander in Azizabad village in Herat's Shindand district.
However, the UN, the Afghan government and an Afghan human rights group said the number of civilian deaths was far higher.
Their estimates of the number of civilians killed varied between 76 and 90, with the UN eventually concluding that children accounted for 60 of the dead.
The dispute over the figures had escalated into a fierce behind-the-scenes battle behind the UN and the Pentagon.
Warning over deaths
Meanwhile, Human Rights Watch said in a report released on Monday that decreased reliance on ground forces and greater use of air power was leading to "mistakes" that had "dramatically decreased" support for the Afghan government and international troops.
"Civilian deaths from air strikes act as a recruiting tool for the Taleban and risk fatally undermining the international effort to provide basic security to the people of Afghanistan," Brad Adams, Asia director of HRW, said in a statement.
Afghan President Hamid Karzai visited Azizabad after the air strike
The group found that in 2007 at least 321 Afghan civilians had been killed in international air strikes - a rise from at least 116 in 2006.
This figure was much lower than the number of civilians killed in militant attacks, the group said. Nearly 950 people were killed by insurgents in 2008, compared with 700 in 2006.
HRW said most of the air strike casualties occurred in unplanned raids, when air power was called to give support to troops on the ground.
"The US and Nato need to dramatically improve their co-ordination with each other and with the government of Afghanistan," HRW's Rachel Reid told the BBC.
Afghan President Hamid Karzai has repeatedly warned the US and Nato that civilian deaths undermine his government and damage the reputation of foreign forces in the country.
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