A U.S. helicopter has crashed late Friday in eastern Afghanistan, killing all 10 American soldiers on board. 

U.S. military officials say the crash late Friday occurred during combat operations in Kunar province. The CH-47 Chinook went down about 240 kilometers east of the capital, Kabul, not far from the Pakistan border.

Military spokeswoman Lieutenant Tamara Lawrence says an investigation is under way to determine the cause of the crash.

"But it is important to note that the crash was not due to any hostile action or enemy fire," she said.

She says the bodies of all 10 soldiers have been recovered.

More than 2,000 U.S. and Afghan soldiers have been targeting al-Qaida and Taleban insurgents in Kunar province since last month. It is one of the largest offensives since the U.S.-led coalition ousted the Taleban from power in 2001.