President Barack Obama said Saturday that the deaths of Americans in a helicopter crash in Afghanistan are a reminder of the "extraordinary" price the U.S. military is paying in the decade-long Afghan war.

Insurgents shot down a U.S. military helicopter during fighting in eastern Afghanistan, killing 30 Americans, most of them belonging to the same elite unit as the Navy SEALs who killed former Al Qaeda leader Usama bin Laden, U.S. officials said Saturday. It was the deadliest single loss for American forces in the decade-old war against the Taliban.