NATO is investigating Taliban claims that they shot down a U.S. army helicopter in central Afghanistan killing 38 people including elite U.S. special forces.

Fighting continued in Wardak province Sunday where the Chinook CH-47 transport helicopter went down a day late Friday. Thirty U.S. troops, including Navy Seals special forces, died in the crash along with seven Afghan commandos and an interpreter.

The Taliban is claiming responsibility for the attack. Local Afghan government forces say the helicopter crashed after being hit by a rocket. The crash took place following a U.S. led raid against a Taliban-controlled compound in which coalition forces killed eight militants.

The attack was the deadliest single loss for coalition troops in the decade-long war.

In separate statements, U.S. Defense Secretary Leon Panetta and NATO Secretary General Anders Fogh Rasmussen said that coalition forces will “stay the course” in Afghanistan.

The NATO alliance has begun transferring security responsibility to Afghan forces in parts of the country as part of a plan to withdraw all NATO combat troops by the end of 2014.

Meanwhile in other violence, NATO say four servicemembers were killed Sunday in two separate insurgent attacks in southern Afghanistan and the country's east.