Fire officials prepared late Sunday for rapid growth of a wildfire blazing 20 miles north of downtown with the expected arrival of strong, dry wind gusts overnight.

"There's been no open flames for hours. It's just smoldering," Los Angeles County Fire Department spokesman Ron Haralson said Sunday night. "We want that to continue, but the winds are going to grow and we risk a flare-up."

The fire, which broke out about 2 a.m. Sunday, burned through 2,066 acres of rugged terrain in the Angeles National Forest, razing a house, a garage, several sheds and three mobile homes. More than 1,200 people were evacuated and advised not to return to their homes overnight.

The fire was 20 percent contained Sunday night and no serious injuries were reported.

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But Haralson warned the situation could easily deteriorate as powerful Santa Ana winds of up to 60 mph (96 kph) were forecast to arrive from inland areas. Gusts could spread embers and ignite parched brush and chaparral as far as a mile away.

A "fire weather watch" was declared Sunday afternoon for all of Southern California except the deserts through Tuesday.

Some 1,000 people were deployed to fight the fire along with water-dumping helicopters and planes.

The blaze threatened neighborhoods around Kagel and Lopez canyons, forcing the evacuation of about 450 homes. Many displaced residents sought refuge at a shelter set up at nearby San Fernando High School. Horses and farm animals were evacuated to Hansen Dam.

"It burned right down to a couple of neighborhoods," said U.S. Forest Service spokesman Stanton Florea.

The fire was burning south of the Wildlife Waystation, an animal sanctuary and rehabilitation facility set on 160 acres. The nonprofit agency houses more than 400 animals, including lions, bears and deer. Officials loaded up the animals ready for evacuation in case the fire switched direction.

"They are packing them up in case they have to go," said U.S. Forest Service spokeswoman Dee Dechert.

The cause of the fire was under investigation.

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