There have always been disagreements because accurately counting the dead in the chaos of Iraq's war has never been easy. Yet discrepancies appear to be widening as the political stakes grow.
U.S. officials privately say that some officials in the Shiite-dominated Interior and Health ministries could possibly have political or personal motives for inflating casualty numbers for bombings in mainly Shiite areas.
Iraqi officials insist their tallies are more accurate, saying the figures are based on death certificates issued by hospitals and the number of wounded who receive treatment.
The increase in attacks comes at a sensitive time for Iraq, with political tensions heating up ahead of provincial elections that are due to be held by Jan. 31 and are expected to shift some power to the disaffected Sunni minority.
Sunni and Shiite extremists also oppose negotiations that are under way over a proposed U.S.-Iraqi security pact that would extend the presence of American forces in the country beyond the end of the year.
U.S. officers acknowledge the difficulties in establishing accurate numbers but express confidence their figures come close thanks to an increased presence of American troops who have spread throughout the community to work with their Iraqi counterparts.
American soldiers race to the site of bombings, often with the Iraqi security forces that are responding to the attacks. Those troops interview witnesses as well as rescue crews to reach a consensus on casualties and the type of attack, the military said.
"We do have enough soldiers throughout the battle space that when there is an explosion, we hear it and basically we run to the sound of the gun," said Lt. Col. Steve Stover, a spokesman for U.S. forces in Baghdad.
If the U.S. military is unable to promptly reach the scene, it depends on casualty reports from American transition teams working with the Iraqi security forces that do.
It's a change from earlier in the war, when American troops focused on fighting insurgents and often declined to provide civilian casualty information.
Adel Muhsin, a top Health Ministry official, said the Americans generally aren't getting the full picture, pointing out that victims often die of their wounds at the hospital or on the way there.
"The U.S. figures are based on the preliminary reports. Usually, the first view is not completely dependable because the site is still chaotic," Muhsin said. "Preliminary and initial figures taken shortly after the explosion tend to be small."
John Pike, a military and security analyst who runs the respected Web site GlobalSecurity.org, said methodology and politics on both sides could be at play in the differing numbers.
He noted that followers of anti-U.S. Shiite cleric Muqtada al-Sadr, a rival of Prime Minister Nouri al-Maliki's government, wield influence in the Health and Interior ministries.
"I could easily imagine that the U.S. government would want to get a low number, which would suggest that peace is at hand, and that al-Sadr might want a high number to suggest that maybe al-Maliki is not doing such a good job after all," Pike said. "You could imagine both methodological and political explanations for the discrepancy."
