One of the deputies involved in a gun battle Tuesday afternoon with fugitive former police officer Christopher Dorner has died of his wounds, law enforcement sources told The Times.

The San Bernardino County sheriff's deputy was airlifted to Loma Linda University Medical Center, where he was pronounced dead, according to the sources.

Another deputy was also wounded in the shootout near a cabin where Dorner was believed to be holed up in the snow-covered mountains near Big Bear. His condition was not immediately known.

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The afternoon gun battle in which hundreds of rounds were exchanged was part of a quickly changing situation that began after Dorner allegedly broke into a home, tied up a couple and held them hostage before fleeing with their white pickup truck, authorities said.

Then Dorner was allegedly spotted by state Fish and Wildlife officers in the pickup truck, sources said. A vehicle-to-vehicle shootout ensued. The officers' vehicle was peppered with multiple rounds, according to authorities.

Dorner crashed his vehicle and took refuge in a nearby cabin, sources said. One deputy was hit as Dorner fired out of the cabin and a second deputy was injured when Dorner exited the back of the cabin, deployed a smoke bomb and opened fire again in an apparent attempt to flee. Dorner was driven back inside the cabin, the sources said.

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He remained inside the cabin Tuesday afternoon as officers swarmed the site.

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-- Phil Willon, Joel Rubin, Andrew Blankstein, Robert J. Lopez and Kate Mather