PRESCOTT, Ariz. -- The 19 firefighters killed last weekend in an Arizona blaze died of burns and inhalation problems, according to initial autopsy findings released Thursday.
Cari Gerchick, a spokeswoman for the Maricopa County medical examiner's office in Phoenix, said the members of the Hotshots crew died from burns, carbon monoxide poisoning or oxygen deprivation, or a combination of the factors.
The autopsies were performed Tuesday, but more detailed autopsy reports should be released in three months, pending lab work.
"Our work is not done," Gerchick said. "But what we are glad about is that we can release these fallen heroes to their families for burial, and that grieving process can continue."
The bodies of the Prescott-based Hotshots will be taken back to the hilltop community in a 75-mile procession from Phoenix on Sunday.
Each firefighter will be in an individual hearse, accompanied by motorcycle escorts, honor guard members and U.S. flags.
A memorial service planned for Tuesday is expected to draw thousands of mourners, including the families of the firefighters.
The firefighters had deployed Sunday to what was thought to be a manageable lightning-caused forest fire near the small town of Yarnell, about 60 miles northwest of Phoenix.
Violent winds turned the fire and trapped the highly trained Hotshots, most of them in the prime of their lives. Fire officials said the crew had deployed their fire shelters, which can briefly protect people from blazes.
It was the nation's biggest loss of firefighters since 9/11.
Nearly 600 firefighters continue to fight the blaze, which was 45 percent contained yesterday morning. The fire has destroyed more than 100 homes and burned about 13 square miles. Yarnell remained evacuated Thursday, but authorities hope to allow residents back in by Saturday.