Hundreds Flee Arson Fire in Central California Area : Blaze: About 950 firefighters battle flames racing toward Atascadero. U.S. 101 is closed in region. L.A. city and county fire departments send personnel and equipment.

A racing arson fire roared toward this Central California city Monday night, prompting several hundred people to flee and raining ash on nearby communities, authorities said.

Help was called in from around the state as firefighters fought to keep the blaze from destroying homes. About 950 firefighters were on the line, accompanied by water-dropping helicopters, said Glenda Powell, a spokeswoman for the California Department of Forestry.

Sixty firefighters from the Los Angeles Fire Department were dispatched to the scene with 10 pieces of equipment to assist in battling the blaze, fire officials said.

The Los Angeles County Fire Department sent 70 firefighters and 15 engines late Monday, a department spokesman said.

“We have unconfirmed reports of structure loss,” said Forestry Department spokesman John Madden.

The fire nearly tripled in size in four hours to about 22,000 acres, said the Forestry Department’s Val Houdyshell.

U.S. 101, one of the state’s main north-south routes, was closed between San Luis Obispo and Atascadero, a town of about 23,000.

An eight-mile stretch that includes the southern end of Atascadero, the small community of Garden Farms and the ranching town of Santa Margarita were evacuated after the flames began racing toward them from neighboring Los Padres National Forest.

“There have been evacuations throughout the afternoon,” said Lt. Pat Hedges of the San Luis Obispo County Sheriff’s Department. He estimated that several hundred people had left by Monday night.

“They’re evacuating an area of probably 500 or 600 families,” said Betty Van Gorder, program coordinator for the San Luis Obispo County chapter of the Red Cross.

Smoke and ash enveloped San Luis Obispo, about 16 miles south of Atascadero, covering cars with a blackish layer, Hedges said.

About 110,000 of 125,000 customers were without power because the fire had burned the main transmission lines, said Arlene Morris-Versaw, a spokeswoman for Pacific Gas & Electric.

“We have no power here. The whole south county has no power” and phone communications are “nearly impossible,” Van Gorder said.

During the day, firefighters--some of them arriving after battling other wildfires in the state--used shovels and bulldozers to hack firebreaks out of 80-year-old brush.

“There is zero containment,” said Bob Bergstrom, a California Department of Forestry spokesman. “We are working on saving lives and property in the day and hope it lays down at night.

“It’s hot, inaccessible and very thick, old brush. This is in a real nasty brush area.”

Temperatures rose to 108 degrees during the day, humidity was low and fickle 15 m.p.h. winds changed directions hourly. There were five injuries to firefighters--three from heat exhaustion and two from ankle sprains.

The fire was deliberately set about 4 p.m. Sunday at the 2,600-foot level off California 41 near the Cerro Alto Campground, fire officials said. The area includes part of Los Padres National Forest and is about 150 miles northwest of Los Angeles.