Fire crews continued efforts to fully contain the 250-square-mile (300-square-km) wildfire burning in the Angeles National Forest on Tuesday.

The arson fire remained 60 percent contained, and it was still listed at 160,357 acres, said Carlos Guerro, spokesman for the unified fire command.

Ground crews continued efforts on Tuesday to build a fire line around the fire's southern perimeter to ensure that foothill communities are adequately protected, the Los Angeles County Fire Department (LACFD) said.

Fire containment lines have been completed on the northeast side of the blaze, protecting thousands of houses, barns and corrals in the Juniper Hills section of the Antelope Valley.

About 4,500 firefighters were still battling the blaze. But for the second day in a row, backfiring operations near Mount Wilson were canceled.

The backfires were originally scheduled for Monday in hopes of destroying some of the dry vegetation that has been feeding the blaze, but the idea was scratched because of a flare-up. The backfires in the Mount Wilson and Cogswell Reservoir areas were rescheduled for Tuesday, but were scrubbed again due to poor weather conditions.

Winds of between 30 and 40 mph caused a flare-up in some areas of San Gabriel Wilderness Monday, prompting the postponement of backfire operations above the city of Pasadena.

"They didn't want to start backfire operations while they're using (water and retardant-dropping) aircraft for the flare-up," LACFD spokesman Darryl Jacobs said.

Fire officials said they will try again to set backfires near Mount Wilson on Wednesday.

Mike Dietrich, the Station Fire incident commander, said a great deal of hard work remains. He also noted that, while cooler temperatures and higher humidity are being felt in the foothills, it continues to be hot and dry at higher elevations.

Fighting the blaze as of Tuesday morning has cost 57.6 million dollars, according to the Forest Service.

Since it broke out two weeks ago, the fire has claimed the lives of two firefighters, injured 11 people and destroyed 78 homes, mostly cabins, two commercial properties and 86 outbuildings.

The Los Angeles County Board of Supervisors will approve a 50,000-dollar reward for the arsonist responsible for the Station Fire, the Los Angeles Times reported at its website on Tuesday.

Earlier California Governor Arnold Schwarzenegger has already established a 100,000-dollar for information on the fire.

According to the newspaper, investigators believe a substance found near the fire's point of origin helped spread the deadly blaze, and it has emerged as a key piece of evidence in the arson probe.

Sources said investigators are going through a database of arson suspects and fire bugs to search for possible suspects.