SANTA CLARITA, Calif., Oct. 31 (UPI) -- A wildfire that burned 38,000 acres and wiped out 21 homes in the Santa Clarita, Calif., area is being blamed on a boy playing with matches.

"We have identified a juvenile boy as the person who started the fire," Los Angeles County Sheriff's Department spokesman Steve Whitmore said Tuesday. "Arson investigators interviewed the young man and he acknowledged he had been playing with matches and accidentally started a fire."

Meanwhile, firefighters were finding success in controlling wildfires burning across southern California, the Los Angeles Times reported. Higher humidity, weak winds and lower temperatures all helped.

"We've had good weather for firefighting," said Rich Phelps, a U.S. Forest Service spokesman. "This is a window of opportunity we have to take."

Seven fires were yet to be contained: the Witch, Harris and Poomacha fires in San Diego County; the Slide and Grass Valley fires in San Bernardino County; the Ranch fire in Los Angeles County; and the Santiago fire in Orange County.

The nearly three dozen southern California fires burned a half-million acres, destroyed 2,786 structures, killed seven people and forced about 500,000 people to evacuate their homes.