The Lockheed P2V, operated by Neptune Aviation of Missoula, Mont., went down shortly before 2 p.m. while working the White Rock fire in the Hamblin Valley area west of Cedar City, KCSG-TV, Cedar City, reported.
The Iron County Sheriff's Office identified the pilots as Capt. Todd Neal Tompkins, 48, and First Officer Ronnie Edwin Chambless, 40, both of Boise, Idaho.
The cause of the crash had not been determined, the TV station said.
In a statement Monday, U.S. Interior Secretary Ken Salazar expressed his "deepest condolences" to the victims' families, friends and co-workers.
"Their loss is a stark reminder of the risks endured by the men and women who fight the wild fires that threaten lives and property across the West, and especially by those who take up that challenge from the air," Salazar said. "The Department of the Interior and the Bureau of Land Management stands ready to assist and support the family and friends of these brave individuals. We will also remain vigilant and continue to do all we can to ensure the safety of all firefighters in this challenging wildfire season."
The U.S. Bureau of Land Management said the White Rock fire was ignited by lightning Friday night near Caliente, Nev., and spread into Utah, burning about 5,000 acres by Saturday, WSL-TV, Salt Lake City, reported.
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