A California wildfire that has destroyed more than a dozen homes and left one man dead is forcing thousands of residents to flee as flames raged for a fourth day through drought-parched canyons and foothills north of Los Angeles, officials said on Monday. The so-called Sand Fire has charred at least 50 square miles (130 square km) around the rugged northwestern fringes of the Angeles National Forest since it broke out on Friday, and remained just 10 percent contained on Monday, authorities said. Since Sunday alone the blaze engulfed an additional 11,000 acres, according to the latest figures from fire managers. At least 18 dwellings burned over the weekend, and the body of one man was found on Saturday evening in a burned-out car parked in the driveway of a home. Plans to begin allowing some displaced residents to return to their communities were canceled late on Sunday after a dangerous shift in the winds. By Monday morning evacuation orders had been expanded to 10,000 homes, or roughly 20,000 people, Los Angeles County Fire Inspector Joey Marron said, adding that about 200 commercial buildings were also in harm's way. Authorities on Sunday had put the number of people evacuated at 1,500. The blaze was threatening a cluster of small communities near Santa Clarita, about 40 miles (65 km) north of Los Angeles, as it cast a pall of smoke and soot over a wide area of the region. Much of the Los Angeles basin was dusted with a thin layer of fine white ash from the fire on Saturday and Sunday. Fed by dense brush desiccated during five years of drought, flames were initially stoked by triple-digit heat and extremely low humidity. Slightly cooler, moister conditions and diminished winds were expected to help firefighters on Monday. Nearly 3,000 firefighters were battling to contain the blaze, the cause of which was under investigation. About 300 miles to the northwest, a separate 10,000-plus-acre fire was burning in a coastal area of Monterey County, prompting authorities to widen evacuation orders to several communities there on Sunday, according to the California Department of Forestry and Fire Protection. One person suffered non-life-threatening injuries and one structure was destroyed, Cal Fire spokeswoman Amber Anderson said.