An Afghan operation to flush out Taliban rebels and showcase growing military competence has turned into a debacle, with many troops dead or captured and commanders pleading for help, The New York Times reported Friday.

A senior US official with knowledge of the mission -- apparently not coordinated in advance with NATO officers -- said commanders called for backup from foreign forces after at least 10 Afghan soldiers were killed and up to 20 captured since the operation began August 3 in a rugged region east of Kabul.

Fighting has raged so intensely over the past week in the area around Bad Pakh village, in Laghman province, that the Red Cross has been unable to reach the battle zone and evacuate the wounded and dead, the Times reported.

"There are several soldiers unaccounted for and killed," a senior American military official was quoted as saying on condition of anonymity because the operation was ongoing.

He said "about 10" soldiers had been killed.

"There are a lot of lessons to be learned here," he said. "How they started that and why they started that."

NATO has reportedly sent in French and American rescue teams.

A high-ranking official in Afghanistan's Ministry of Defense said the military's plan was betrayed, and that Taliban fighters were lying in wait to ambush the bulk of the 300 men from the First Brigade of the 201st Army Corps.

The ministry's spokesman, Major General Muhammed Zahair Azimi, said seven soldiers had died and that an unknown number were taken prisoner.

"We can not say the number captured because some of them were in difficult places, but some of our soldiers were captured by the Taliban," Azimi said Wednesday, according to the Times.

A Taliban spokesman said 27 Afghan soldiers were killed, 14 wounded and eight captured, the paper reported. The Taliban often exaggerates its claims of damage and casualties.

The mission marks a major embarrassment for the Afghan army, which said this week it has met a target of 134,000 troops two months ahead of schedule, and as it gears up to take responsibility for security from US-led NATO forces by 2014.

Despite its steady expansion of operational capacity, the Afghan army runs few major missions on its own.

Afghanistan's troops are at similar force size to NATO troops on the ground. War monitor group iCasualties says 521 coalition soldiers were killed in Afghanistan in 2009, while the Times reported 282 Afghan soldiers were killed.