Four firefighters were killed, and a fifth is in grave condition.
BEAUMONT, Calif. (AP) -- As flames roared through the canyons of Southern California, authorities increased the reward to $500,000 Friday for the arrest of the arsonist responsible for the deaths of four firefighters in the nation's worst such tragedy in five years.
A fifth firefighter lay in grave condition with burns over 90 percent of his body.
Firefighters labored through thick smoke as curtains of wind-whipped orange flame pushed through uninhabited brushland about 90 miles east of Los Angeles. The blaze that broke out Thursday destroyed about 10 structures, including homes, forced 700 people to flee, and flushed coyotes and other wildlife into the open.
Investigators have not said how they know the nearly 40-square-mile blaze was arson, how it was set, or why. But they said those responsible could face murder charges.
Two young men were seen leaving the area where the fire broke out about 1 a.m. Thursday. Also, investigators said they were looking into whether the wildfire was related to other blazes in recent months, including a canyon fire last weekend.
More than 1,700 firefighters worked to corral the advancing flames. Winds gusted to 45 mph but kept the flames moving through undeveloped land, away from homes in Riverside County. Mop-up work was under way back in the mountain communities where the flames swept through the previous day. Hundreds of people were allowed to leave an RV park where they had taken refuge, and many other families were able to return to their homes. About 400 people remained evacuated Friday evening.
The U.S. Forest Service firefighters were killed Thursday when the wind blew a wall of flames down on them in the hills near Palm Springs as they tried to protect a home.
It was the worst disaster involving firefighters battling a wildfire since 2001, when four firefighters were trapped by flames and killed in Washington state.
James Pence, 63, said that shortly after the fire started in the town of Cabazon, he saw two unfamiliar young men leaving the area, which he said is close to a teenage hangout known as Raccoon Rock. "These kids didn't belong here. They were strange people," Pence said.
Tim Bowers, 49, said he was awakened by his dog, looked outside his trailer and saw flames on a hillside about 100 yards away. He said two unfamiliar young men walked away from the fire.
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