The sun sets through smoky skies from the so-called Bluecut Fire in the San Bernardino National Forest. Picture: REUTERS/Gene Blevins
The sun sets through smoky skies from the so-called Bluecut Fire in the San Bernardino National Forest. Picture: REUTERS/Gene Blevins
Thick smoke from the Bluecut Fire fills the sky near the San Bernardino National Forest. Picture: REUTERS/Gene Blevins
Thick smoke from the Bluecut Fire fills the sky near the San Bernardino National Forest. Picture: REUTERS/Gene Blevins
A man calms his horse on the streets while evacuating from the Bluecut Fire. Picture: REUTERS/Gene Blevins
A man calms his horse on the streets while evacuating from the Bluecut Fire. Picture: REUTERS/Gene Blevins
A firefighter watches the Bluecut Fire. Picture: REUTERS/Gene Blevins
A firefighter watches the Bluecut Fire. Picture: REUTERS/Gene Blevins
A chicken coop goes up in flames with animals still inside (not pictured) at the so-called Bluecut Fire. Picture: REUTERS/Gene Blevins
A chicken coop goes up in flames with animals still inside (not pictured) at the so-called Bluecut Fire. Picture: REUTERS/Gene Blevins
A melted sign from a McDonald's restaurant shows the damage as firefighters check the area after a wildfire swept through Cajon Junction, California. Picture: EPA/EUGENE GARCIA
A melted sign from a McDonald's restaurant shows the damage as firefighters check the area after a wildfire swept through Cajon Junction, California. Picture: EPA/EUGENE GARCIA
A firefighter keeps an eye on the Bluecut fire line. Picture: EPA/PAUL BUCK
A firefighter keeps an eye on the Bluecut fire line. Picture: EPA/PAUL BUCK

By Dan Whitcomb and Alex Dobuzinskis

Los Angeles -Authorities in southern California ordered the evacuation of 82,000 people on Tuesday, after a wildfire broke out in a mountain pass to rapidly engulf 6,070 hectares of terrain.

Officials said about 700 firefighters were battling to control the blaze in an area called the Cajon Pass, the latest in a series of wildfires that have blackened nearly 121,400 hectares of the drought-parched US West.

"It is a very fast-moving fire, it has wind behind it," said US Forest Service spokeswoman Lyn Sieliet.

Two firefighters were trapped by flames in the effort to evacuate residents and defend homes, but managed to escape with only minor injuries, fire officials said.

The so-called Bluecut Fire erupted in heavy brush just west of Interstate 15, the main freeway between Las Vegas and the Los Angeles area, forcing the closure of one stretch of the highway.

The inferno prompted orders for residents of the community of Wrightwood, 120km east of Los Angeles, to leave their homes, said Lynne Tolmachoff, of the California Department of Forestry and Fire Protection (Cal Fire).

In all, about 82,000 people were ordered to flee, as flames destroyed an unknown number of houses, the Cal Fire spokeswoman said by telephone.

The fire remained unchecked, having exploded within hours to cover an area of 6,070 hectares, Cal Fire said, up from an estimate of 3,640 hectares on Tuesday evening.

The Bluecut Fire, whose cause officials said they were still investigating, came as crews more than 970km to the northwest began to make headway against a Northern California wildfire that has destroyed more than 175 homes and businesses.

The so-called Clayton Fire was 35 percent contained, according to Cal Fire. It has charred 1,620 hectares in and around the community of Lower Lake, forcing hundreds of people to flee.

Damin Pashilk, a 40-year-old arrested on suspicion of setting that blaze, and several others in the area over the past year, is set to appear in court on Wednesday.

Fierce winds fanned the fire, which threatened about 1,500 structures at its peak, after it sparked on Saturday evening. As of Tuesday evening, only 380 buildings were in danger, according to Cal Fire. There were no reports of casualties.

California Governor Jerry Brown declared a state of emergency in San Bernardino County for the Bluecut Fire, which allows state agencies to come to the assistance of local officials.

On Monday, Brown issued emergency declarations for the Clayton fire and another in Central California, the so-called Chimney fire.

The Chimney Fire was 20 percent contained by Tuesday evening, after scorching 2,792 hectares since Saturday. It has destroyed about 40 structures.

Reuters