LOS ANGELES (Reuters) – A fierce California wildfire drove thousands more residents from their homes on Monday as flames raged for a fourth day through drought-parched canyons and foothills north of Los Angeles.

Nearly 3,000 firefighters were battling the so-called Sand Fire, which 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, authorities said.

It remained just 10 percent contained on Monday.

Since Sunday alone the blaze engulfed an additional 11,000 acres, according to the latest figures from fire managers.

A firefighting helicopter makes a water drop at the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn

At least 18 dwellings were destroyed over the weekend, and authorities have reported one fatality, an unidentified man found on Saturday evening in a burned-out car parked in the driveway of a home.

Crews battle the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn

Plans to begin allowing some displaced residents to return to their communities were canceled late on Sunday after a dangerous shift in the winds.

A firefighting helicopter passes over the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn

By Monday morning evacuation orders had been expanded to about 10,000 homes, encompassing an estimated 20,000 to 30,000 people, fire officials said. Los Angeles County Fire Inspector Joey Marron added that about 200 commercial buildings were also in harm’s way.

Authorities on Sunday had put the number of people evacuated at 1,500.

A firefighting aircraft drops fire retardant on the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn

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.

A DC-10 firefighting aircraft flies at dusk during the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn

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.

“Morale from what I can tell is high. They’re working hard, they’re tired, it’s hot, it’s dry,” battalion fire chief Marc Peebles told local television station KABC-TV. “Firefighters are looking for an opportunity to go direct on this fire and knock this thing out.”

Fire burns brush on a hillside during the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn

The cause of the Sand Fire was under investigation. But it is one of some 3,750 blazes large and small to have erupted across California since January, a higher-than-normal total, collectively scorching more than 200,000 acres, state fire officials said.

People take pictures of a firefighting helicopter during the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn

The biggest so far was last month’s Erskine Fire, which consumed 48,000 acres in Kern County northeast of Bakersfield, killing two people and destroying about 250 structures.

By comparison, the October 2003 Cedar Fire ranks as the biggest and one of the deadliest on record in the state. It blackened more than 273,000 acres, leveled 2,820 buildings and claimed 15 lives.

A firefighter battle flames at the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn
A firefighting helicopter makes a water drop at the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn
A firefighter gestures during the so-called Sand Fire in the Angeles National Forest near Los Angeles, California
REUTERS/Jonathan Alcorn
A firefighter checks a home that was burned in the so-called Sand Fire in the Angeles National Forest near Los Angeles
REUTERS/Jonathan Alcorn

A home that was burned is pictured in the so-called Sand Fire in the Angeles National Forest near Los Angeles
REUTERS/Jonathan Alcorn