Navy Chopper on Rescue Mission

Anja Niedringhaus / AP Photo

In this file photo, a Chinook helicopter leaves after dropping supplies for US Marines at Forward Operating Base Edi in the Helmand province of southern Afghanistan, June 9, 2011.

The U.S. helicopter that was tragically destroyed Saturday was on a rescue mission assisting an army unit when it came under fire by insurgents, two U.S. officials told The Guardian. Thirty Americans and eight Afghans were killed in the crash, making it the deadliest single loss for the U.S. in the decade-long war. Twenty-two of the men killed were Navy SEALs. NATO began recovering the remains of the transport helicopter Sunday as forces continued to battle insurgents in the area. NATO also reported the deaths of four alliance members in two separate instances elsewhere Afghanistan.