Under a Freedom of Information request, the U.S. military told the newspaper a database of "significant acts" showed 19,429 militants were killed in clashes with coalition forces, although the numbers don't include those killed during the first wave of the invasion that toppled Iraqi leader Saddam Hussein.

During the same period, 3,800 U.S. troops have been killed, along with 300 others from Britain and other coalition countries, figures from the independent Iraq Coalition Casualty Count Web site showed.

For this year, insurgent deaths totaled 4,882, which is 25 percent higher than all of last year, the military said.

Military officials attribute the hike to several large offensives made possible by the addition of 30,000 troops in February, the newspaper said.