Updated at 7:00 p.m. Eastern
A U.S. military helicopter crashed Monday while returning from the scene of a firefight with suspected Taliban drug traffickers in western Afghanistan, killing 10 Americans including three DEA agents in a not-so-noticed war within a war.
Four more troops were killed when two helicopters collided over southern Afghanistan, making it the deadliest day for U.S. forces in this country in more than four years.
U.S. military officials insisted neither crash was believed a result of hostile fire, although the Taliban claimed they shot down a U.S. helicopter in the western province of Badghis.
"We don't believe that either one of them were due to enemy fire or hostile intent we are still investigating the cause of it," Col. Wayne Shanks told CBS News correspondent Mandy Clark.
However, the Taliban commander's claim that the helicopter was hit with heavy machine gun fire and a rocket propelled grenade while it was low to the ground seems to be consistent with what happened, says CBS News chief foreign affairs correspondent Lara Logan.
"There were a number of survivors," Logan said. "When a helicopter is hit high up in the air and has a catastrophic crash to the ground, usually there are no survivors. Here there were a significant number of survivors, 12 Afghans and a number of Americans as well."
The U.S. did not say where in western Afghanistan its helicopter went down, and no other aircraft were reported missing.
The survivors were rescued by a second Chinook on the same mission. CBS News has been told that an operation has been mounted to reclaim the bodies of the dead and secure the wreckage.
The second crash took place when two U.S. Marine helicopters - a UH-1 and an AH-1 Cobra - collided in flight before sunrise over the southern province of Helmand, killing four American troops and wounding two more, Marine spokesman Maj. Bill Pelletier said.
One of the dead was Marine pilot Captain Kyle VanDeGiesen, a 29-year-old based at Camp Pendleton in San Diego, reports Clark. A family spokesman said he and his wife were expecting their second child.
The casualties marked the Drug Enforcement Administration's first deaths since it began operations here in 2005. Afghanistan is the world's largest producer of opium - the raw ingredient in heroin - and the illicit drug trade is a major source of funding for insurgent groups.
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The U.S. has decided to target production and distribution networks after programs to destroy poppy fields did little except turn farmers against the American-led NATO mission.
NATO said the helicopter containing the DEA agents was returning from a joint operation that targeted a compound used by insurgents involved in "narcotics trafficking in western Afghanistan."
"During the operation, insurgent forces engaged the joint force and more than a dozen enemy fighters were killed in the ensuing firefight," a NATO statement said.
Eleven Americans, including another DEA agent, and 14 Afghan security troops were wounded in the crash, NATO said.
Military spokeswoman Elizabeth Mathias said hostile fire was unlikely because the troops were not receiving fire when the helicopter took off. She said troops had been rushed to the crash site to determine the cause.
The crash came less than a week after a U.N. report found that the drug trade is enabling the Taliban to make more money now than when they ruled Afghanistan before the U.S. invasion in 2001. The DEA sent more agents to Afghanistan this year to take part in military operations against insurgents who use drug smuggling to raise funds for their war against NATO and its Afghan allies.
It was the heaviest single-day loss of life since June 28, 2005, when 19 U.S. troops died, 16 of them aboard a Special Forces MH-47 Chinook helicopter that was shot down by insurgents.
U.S. forces also reported the deaths of two other American service members Sunday: one in a bomb attack in the east, and another who died of wounds sustained in an insurgent attack in the same region. The deaths bring to at least 47 the number of U.S. service members who have been killed in October.
This has been the deadliest year for international and U.S. forces since the 2001 invasion to oust the Taliban. Fighting spiked around the presidential vote in August, when 51 U.S. soldiers died that month - the deadliest for American forces in the eight-year war.
Afghanistan is a punishing environment for helicopters - this month alone the U.S. Army says it has lost six other helicopters - five to crashes, one to enemy fire, Clark reports.
All of this comes as U.S. forces battle a steady erosion of Afghan public support, Clark reports. For the past two days, nationwide protests have been held against U.S. troops accused of burning the Koran. It's an accusation U.S. forces deny and blame the Taliban for whipping up anti-American sentiment.
President Barack Obama mourned 14 Americans killed Monday and told a military audience he will not be hurried as he evaluates whether to alter U.S. strategy in the war.
"I will never rush the solemn decision of sending you into harm's way. I won't risk your lives unless it is absolutely necessary," Obama said during a visit to Naval Air Station Jacksonville in Florida.
Mr. Obama is debating whether to send tens of thousands more troops to the country to curb the burgeoning Taliban-led insurgency. Doubts about bolstering the U.S. force grew after widespread fraud marred the Aug. 20 presidential election, raising doubt whether the U.S. and its NATO allies had a reliable partner in the fight against the militants.
Afghan officials scheduled a between President Hamid Karzai and challenger Abdullah Abdullah after U.N.-backed auditors threw out nearly a third of the incumbent's votes, dropping him below the 50 percent threshold required for a first-round win in the 36-candidate field.
Abdullah complained Monday that there were no assurances that the November vote would be fairer than the first balloting. He called for the head of the government's Karzai-appointed election commission chairman, Azizullah Lodin, to be replaced within five days, saying he has "no credibility."
Lodin has denied allegations of bias in favor of Karzai, and the election commission's spokesman has already said Lodin cannot be replaced by either side.
Another flawed election would cast doubt on the wisdom of sending in more U.S. troops.
With less than two weeks to go until the vote, disagreements have emerged between the U.N. and the Afghans on how to conduct the balloting.
Lodin said the commission hopes to open all 23,960 polling stations from the first round. The U.N. wants to open only 16,000 stations to cut down on the number of "ghost polling stations" that never opened but were used to stuff ballot boxes.
Meanwhile, security forces in Kabul fired automatic rifles into the air for a second day Monday to contain hundreds of stone-throwing university students angered over the alleged desecration of Islam's holy book, the Quran, by U.S. troops during an operation two weeks ago in Wardak province. Fire trucks were also brought in to push back protesters with water cannons. Police said several officers were injured in the mayhem.
U.S. and Afghan authorities have denied any such desecration and insist that the Taliban are spreading the rumor to stir up public anger. The rumor has sparked similar protests in Wardak and Khost provinces.
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