The Taliban has claimed credit for the crash, saying it shot down the helicopter.
KABUL, Afghanistan (AP) -- A U.S. CH-47 Chinook transport helicopter, which a military official said may have been carrying 15 to 20 people, crashed Tuesday while ferrying reinforcements to fight insurgents in a mountainous region in eastern Afghanistan. The Taliban claimed to have shot down the aircraft.
The fate of those on board the helicopter, which crashed near Asadabad in Kunar province, was not immediately known, the U.S. military said. A statement said the cause of the crash was unclear.
Other helicopters and fixed-wing aircraft were sent to the crash site, the military said. Other details were not available, according to U.S. military spokesman Lt. Col. Jerry O'Hara.
In Washington, a U.S. military official said early reports indicated 15 to 20 people were on board. There was no word on their condition, the official said, speaking on condition of anonymity because it involved initial operational reports.
Provincial Gov. Asadullah Wafa told The Associated Press that the Taliban downed the aircraft with a rocket. He gave no other details.
Purported Taliban spokesman Mullah Latif Hakimi telephoned the AP before news of the crash was released and said the rebels shot the helicopter down.
Hakimi often calls news organizations to claim responsibility for attacks on behalf of the Taliban. His information has sometimes proven untrue or exaggerated, and his exact tie to the group's leadership is unclear.
The crash was the second of a Chinook helicopter in Afghanistan this year. On April 6, 15 U.S. service members and three American civilians were killed when their chopper went down in a sandstorm while returning to the main U.S. base at Bagram.
The U.S. military has launched operations in several areas along the border with Pakistan. Those offensives target remnants of Al-Qaida and the hard-line Taliban movement, as well as foreign fighters using high mountain passes to cross the largely uncontrolled border from Pakistan.
Tuesday's crash comes after three months of unprecedented fighting that has killed about 465 suspected insurgents, 29 U.S. troops, 43 Afghan police and soldiers and 125 civilians.
Afghan and U.S. officials have predicted that the situation will deteriorate in the lead-up to legislative elections in September.
Meanwhile, landmark legislative elections in Afghanistan will be held as planned in September despite an upsurge in rebel violence that has raised fears the polls could be threatened, the president's spokesman said Tuesday.
President Hamid Karzai's spokesman said that the elections "will be successful."