CORONA, Calif. - Firefighters are making good progress in their efforts to contain an 800-acre wildfire in the dry, brown hills in western Riverside County.

The blaze, which broke out east of Corona Thursday afternoon, was 50 percent contained late Thursday. Full containment was expected by 6 a.m. Friday.

No homes were immediately threatened, but the county Fire Department urged residents to be prepared in case an evacuation was needed.

Gentle winds pushed the flames away from homes.

Authorities say the fire was sparked by mowing and brush clearing equipment.

The National Weather Service says strong, gusty winds are expected Friday in other parts of Southern California, with "red flag" warnings for fire-weather conditions in some mountain and desert areas.

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