(AP) KABUL, Afghanistan - A spokesman for the NATO coalition in Afghanistan says it's investigating the cause of today's crash of a Black Hawk helicopter in Kandahar province that killed seven American troops and four Afghans.
U.S. officials say initial reports indicated that the chopper was not shot down.
But the Taliban claim that their fighters did, in fact, shoot down the aircraft.
The crash marked another deadly day for the U.S. in Afghanistan, less than a week after six American service members were gunned down apparently by two members of the Afghan security forces they were training.
The spike in U.S. deaths and the attacks from within the Afghan military have raised fresh doubts about the U.S. plan to leave a capable Afghan government in place when most U.S. and coalition troops depart.
The province where today's crash took place is a traditional Taliban stronghold. It's the spiritual birthplace of the hardline Islamist movement.
U.S. officials say three of the seven Americans who were killed were special operations forces two Navy SEALS and a Navy explosives expert.
Kandahar is a traditional Taliban stronghold and the spiritual birthplace of the hardline Islamist movement that ruled Afghanistan before being ousted in 2001 by the U.S.-led alliance for sheltering al Qaeda's terrorist leaders.
U.S. officials said three of the seven American troops killed were special operations forces two Navy SEALS and a Navy explosives expert. The officials spoke on condition of anonymity because they were not authorized to disclose the information.
Taliban spokesman Qari Yousef Ahmadi said insurgent fighters shot down the helicopter in Kandahar province on Thursday morning.
"Nobody survived this," Ahmadi told The Associated Press by phone.
The helicopter was shot down in Kandahar's Shah Wali Kot district, which lies in the northern part of the province, said Ahmad Jawed Faisal, a spokesman for the provincial government said. He declined to give further details.
However, U.S. officials said initial indications are that it was not shot down, though an investigation has been opened. The officials spoke on condition of anonymity the investigation is ongoing.
White House spokesman Jay Carney said it was too early to determine the cause of the crash.
"Based on my information, at this time the cause of that crash is still under investigation," Carney said. "Of course our thoughts and prayers are with those American and Afghan families who lost loved ones in that incident."
The area where the helicopter went down a stretch of Kandahar along the border with Uruzgan province is seen as a Taliban stronghold and key transit route. The insurgents regularly attack police checkpoints around the rural villages of the district and plant bombs in the road to catch passing government vehicles.
The Sikorsky UH-60 Black Hawk is a medium-lift helicopter that has served as the U.S. Army's workhorse since the 1980s.
The U.S.-led NATO force in Afghanistan has relied heavily on utility helicopters such as the Black Hawk to ferry troops, dignitaries and supplies around the mountainous terrain, thus avoiding the threat of ambushes and roadside bombs.
Thursday's crash is the deadliest since a Turkish helicopter crashed into a house near the Afghan capital, Kabul, on March 16, killing 12 Turkish soldiers on board and four Afghan civilians on the ground, officials said.
In August last year, insurgents shot down a Chinook helicopter, killing 30 American troops, mostly elite Navy SEALs, in Afghanistan's central Wardak province.
At least 221 American service members have been killed in Afghanistan so far this year.