The weeklong operation, which concluded over the weekend, was aimed at rebels in the eastern Koregnal Valley believed responsible for twin attacks that killed 19 troops in June. Three Navy SEALs were killed in an ambush, and all 16 soldiers on a helicopter sent to rescue them died when it was hit by a rocket-propelled grenade.
"It was successful," Lt. Col. Jerry O'Hara told The Associated Press. "We had over 29 separate engagements with enemy forces that resulted in more than 40 enemy killed in action and many others wounded."
O'Hara also announced that a separate three-day battle from Aug. 7-10 in southern Zabul province's Daychopan district left a total of 65 suspected militants dead. The military had previously reported that 16 rebels had been killed.
News of the casualties comes after a deadly period for U.S. forces in Afghanistan, with 13 American troops killed this month. Four soldiers were killed Sunday when a massive bomb exploded under a wooden bridge as a convoy of armored Humvees was crossing it. Three troops were wounded by shrapnel from secondary explosions as they tried to pull the four out of a burning Humvee.
Most of the troops who have been killed were part of an offensive against militants who have vowed to subvert legislative elections on Sept. 18 — the next step toward democracy after more than two decades of war and civil strife.
Some 187 U.S. service members have been killed in and around Afghanistan since the start of Operation Enduring Freedom in late 2001 — including 64 during a rash of insurgent attacks in the last six months, which have left about 1,000 other people dead as well.
The bloodshed has led the military to rush in an airborne infantry battalion of about 700 troops on standby in Fort Bragg, N.C., boosting the number of American troops in Afghanistan to about 20,000. Some 3,100 soldiers from 19 other nations also are members of the U.S.-led coalition.
The recent violence in Afghanistan pales next to the casualties suffered in Iraq, but it has dampened some of the optimism that prevailed after the country's inaugural presidential election took place took place peacefully last fall and insurgent attacks dropped off during the winter.
In other recent developments: