The Associated Press

WEAVERVILLE, Calif. — Authorities on Sunday finished collecting badly burned remains from the crash site of a firefighting helicopter in the Northern California wilderness.

A day earlier, helicopters carrying flag-draped stretchers that bore some of the remains were greeted by an honor guard of firefighters at a nearby airstrip.

Accompanied by a fire engine escort, the stretchers were taken to the Shasta County coroner's office in Redding. Authorities there would probably have to rely on DNA analysis and dental records to identify the bodies, U.S. Forest Service spokesman Tom Kroll said.

Nine people were killed in the crash.

The helicopter was ferrying 10 firefighters, two pilots and a U.S. Forest Service employee back to base camp Tuesday after crews battled a fire about 215 miles northwest of Sacramento.

The Sikorsky S-61N helicopter had just been refueled when it lifted off from a remote clearing, struck a tree and plummeted into a hillside, according to National Transportation Safety Board officials. The chopper then erupted into flames.

Two of the four men who survived the crash, firefighters Michael Brown, 20, and Jonathan Frohreich, 18, both of Medford, Ore., were discharged from the University of California Davis Medical Center in Sacramento on Saturday. They suffered facial burns and broken bones.

Brown said Saturday that he couldn't remember anything about the crash but felt that he was spared because "God had his hand wrapped around me."

He said he was mourning the loss of friends: "Those guys were brothers to me."

Pilot William Coultas of Oregon has undergone skin grafting for severe burns. He was in critical condition Sunday, said Martha Alcott, a spokeswoman for UC Davis Medical Center in Sacramento.

Crews also worked Sunday to extract the shell of the helicopter from the rugged terrain, said Forest Service spokesman Bernie Pineda. The pieces will be examined by NTSB investigators.

"It will be a long time before they can piece everything together and determine the accident's cause," Pineda said.

A cockpit voice-data recorder recovered from the wreckage Thursday was made by a British company and was being sent to Britain for analysis, NTSB officials said.

The 34-square-mile blaze the firefighters had been battling before their helicopter crashed was 20 percent contained Sunday, fire officials said.