The number of
It did not identify the 2,500th casualty, in line with US policy not to release details until 24 hours after the family has been informed.
A Pentagon statement said 1,972 of those who died were killed in action.
The campaign group Iraq Body Count estimates that the number of civilians killed since the outset of the conflict ranges between 38,355 and 42,747.
It makes its calculation on the basis of media reports, and believes it to be a conservative estimate.
Other reports put the number of civilian casualties much higher.
Thousands of Iraqi security forces, military personnel from other countries, and Iraqi and foreign fighters have also died.
'Tremendous sacrifice'
Between November 2005 and March 2006, the number of US military fatalities fell month-by-month, as fighters seemed to focus attacks on Iraqi security forces and civilians.
However, they jumped back above the average for April and May. The Pentagon put the blame on a recent surge in rebel violence.
Polls in the
The Pentagon notes that the death rate for US troops is much lower than those in the
In each of those conflicts more than 50,000
"It's important to remember that there is a mission, and there is a greater good which sometimes necessitates tremendous sacrifice," said the
"Rather than focus on an aggregate number, I think it's more important for us to remember that there are individuals in that aggregate number... to whom we should be very, very grateful, and to their families."
The US Senate on Thursday approved 65.8bn dollar for military operations in
Since the 9/11 attacks, the US has now spent or allocated 438bn dollar on its "war on terror", with more than 70 per cent spent in Iraq.
Photo Caption
A coffin of a