Saturday deadliest day for US in 10 years of war

LESTER HOLT, anchor: After 10 years of war, today will sadly be remembered as the single deadliest day for American forces in Afghanistan . The Pentagon confirms that 30 US troops , seven Afghan troops and an Afghan interpreter were killed when their helicopter was shot down as they were responding to assist other troops caught in a fire fight with the Taliban . The dead include 22 Navy SEALs , some of them members of the legendary SEAL Team Six , the unit credited with the killing of Osama bin Laden in Pakistan earlier this year. The horrible news comes at the end of a week in which those of us back home were focused on the country's debt, falling stock prices and partisan squabbling. And now this brutal reminder we are still a country at war with 98,000 American troops putting their lives on the line in Afghanistan every day. We begin our coverage from our Kabul bureau and NBC 's Atia Abawi . Atia , good evening.

ATIA ABAWI reporting: Good evening, Lester . The Taliban quickly claimed responsibility for today's attack, stating that its fighters shot down the helicopter with a rocket. The American and Afghan special forces were working side by side when their operation took a deadly turn. A senior American official says the team was on its way to a mission now far from Kabul , in the Sayedabad district of Wardak province , a volatile region known for its strong Taliban presence. Their

target: a Taliban compound housing insurgent fighters. But soon, their CH-47 Chinook helicopter came under fire and crashed, killing everyone on board. In operations like this one, helicopters can be especially vulnerable.

Colonel JACK JACOBS, Retired (NBC News Military Analyst): This helicopter, like any helicopter, it can go pretty fast in a straight line, but when it is over a target area, when it is inserting itself into a target area, it is slow and it is a very, very easy target for enemy troops on the ground.

ABAWI: The 38 people killed included 22 US Navy SEALs , five Army air crewmen, three Air Force airmen, as well as seven Afghan commandos and an interpreter. A dog, part of the Navy SEAL team, was also killed. The US Navy SEALs were from at least two different units and reportedly included some from SEAL Team Six , the unit involved with hunting down and killing Osama bin Laden in Pakistan back in May. But none of those killed was believed to be part of the bin Laden operation. President Obama was briefed on the attack and expressed condolences to the families of those killed. "The deaths," he said in a statement, "are a reminder of the extraordinary sacrifices made by the men and women of our military and their families, including all who have served in Afghanistan ." As the United States draws down its presence in the country, the special forces are expected to become even more important.

Col. JACOBS: The president of the United States says we're leaving Afghanistan and indeed, we have begun to leave. And what are we going to leave behind? We're going to leave behind special operations forces .

ABAWI: Although NATO deaths have decreased slightly this year in Afghanistan , this latest attack demonstrates just how dangerous the country remains, even for the most elite American and Afghan forces . Both US and NATO officials continue to investigate just what went wrong and how today became the most devastating day for American troops in Afghanistan .

Lester: Atia Abawi in Kabul for us tonight, thanks.

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