Nearly a dozen people are believed to be dead -- with the Los Angeles County sheriff saying he expects that number to rise -- as devastating fires spread across Southern California amid dry and windy conditions,

Ten confirmed deaths and more than 9,000 structures have been damaged or destroyed and more than 150,000 people remain under mandatory evacuation orders. Law enforcement sources told The Times that it’s likely many of the small fires will turn out to have been the work of arson.

The deadly wildfires roaring through Los Angeles County entered a fourth day on Friday. At least 10 people have been killed, about 150,000 are under mandatory evacuation orders and more than 10,000 homes and other structures have been destroyed,