LAKE ELSINORE, Calif. (AP) — Aircraft turned hillsides red with retardant as homeowners wet their houses with garden hoses in a battle to contain an arson wildfire, which prompted evacuation orders for more than 20,000 people south of Los Angeles.

Gov. Jerry Brown declared a state of emergency Thursday night for Orange and Riverside counties as a four-day-old fire carved its way along ridges and hillsides of the Cleveland National Forest.

Brown’s proclamation said thousands of homes were threatened by the fire in the foothills above Lake Elsinore and nearby communities and ordered state agencies to help local governments.

Firefighters planned to work through the night to gain ground against the blaze before the expected return of blustery winds this afternoon that might drive the flames to new ferocity.

A resident of Holy Jim Canyon in the forest was scheduled for a court hearing Friday on charges that he deliberately set the fire.