Updated

Aided by relatively mild weather, hundreds of firefighters made slow but steady progress Sunday against a wildfire (search) crackling through brush and timber that hadn't burned in nearly 50 years.

The fire, burning in the San Bernardino National Forest (search) about 60 miles east of Los Angeles, was 15 percent contained Sunday after scorching approximately 1,352 acres, said Marc Stamer, a fire information officer with the U.S. Forest Service.

Temperatures in the 90s on Saturday fell to the high 50s before dawn Sunday while humidity rose to above 50 percent, Stamer said. He added that firefighters were racing to try to get as much of a perimeter line around the fire as they could before hot, dry weather returned.

At one point, the blaze had threatened as many as 1,500 homes, prompting the evacuation of the 400 closest to the flames. Many of the residents forced to leave likely wouldn't be allowed to return before Monday, Stamer said.The fire also threatened as many of 3,000 outbuildings, destroying one.

"We're mentally prepared for at least two days," said one evacuee, Woody Andrews of Running Springs. The 50-year-old contractor was staying at the Lake Arrowhead Hilton Resort, which had made rooms available to evacuees for $19 a night.

"They have a pool and cable. It's nice," said Andrews.

Dozens of other evacuees stayed at a nearby high school.

In all, about 1,000 people were displaced, Stamer said.

The fire started Friday afternoon about four miles from Highland, in an area with thousands of dead trees that were ravaged by an infestation of Western pine bark beetles, said Karen Terrill, fire information officer for the California Department of Forestry and Fire Protection (search).

"The last time this area burned was 1956, so this is a lot of very dead, very dry material that's burning now, in addition to the bug kill area," she said.

Gene Zimmerman, a Forestry Service supervisor, said more such fires are likely for years to come because of the dry conditions in the area caused by persistent drought.

"We're primed for disaster," Zimmerman said. "It's taken 100 years to get in this condition. It'll take us 30 years to get out of it."

Rebecca Smith, a teacher from Running Springs who was forced to evacuate, said more should have been done to clear the dead trees and dry brush.

"So many people here can't afford to take down dead trees," said Smith, 53. "It was a disaster waiting to happen. So many trees have to come down to keep us safe. It's very frustrating."

More than 850 firefighters using 37 engines, 26 tankers, 14 air tankers, five helicopters, nine bulldozers and 18 water tenders battled the blaze. One firefighter suffered a back injury and eight others suffered various unspecified injuries.

The cause of the fire was not immediately known but Stamer said the cost of fighting it as of Sunday was $975,000. The Federal Emergency Management Agency said it would make disaster relief funding available.