LOS ANGELES: Wildfire threatened 12,000 suburban homes and rained ash on cars as far away as downtown Los Angeles on Sunday, spreading in all directions in hot, dry conditions. Gov. Arnold Schwarzenegger urged those in the fire's path to listen to authorities and get out.

Firefighters fixed their attention on the blaze's fast-moving northern front as more evacuations were ordered.

While thousands have fled, two people who tried to ride out the firestorm in a backyard hot tub were critically burned. The pair in Big Tujunga Canyon, on the southwestern edge of the fire, "completely underestimated the fire" and the hot tub provided "no protection whatsoever," Sheriff's spokesman Steve Whitmore said Sunday.

The two individuals made their way to firefighters and were airlifted out by a sheriff's rescue helicopter. They received adequate notification to evacuate from deputies but decided to stay, Whitmore said.

One of the two was treated and released and the other remained hospitalized in stable condition. A third person was burned Saturday in an evacuation area along Highway 2 near Mount Wilson, officials said. Details of that injury were not immediately known.

"There were people that did not listen, and there were three people that got burned and got critically injured because they did not listen," Schwarzenegger said at a news conference at the fire command post.

The blaze was only about 5 percent contained and had scorched 55 square miles in the Angeles National Forest. Mandatory evacuations were in effect for neighborhoods in Glendale, Pasadena and other cities and towns north of Los Angeles. Officials said air quality in parts of the foothills bordered on hazardous.

At least three homes deep in the Angeles National Forest were confirmed destroyed, but firefighters were likely to find others, Dietrich said.

Firefighters hoped to keep the blaze from spreading up Mount Wilson, where many of the region's broadcast and communications antennas and a historic observatory are located. Flames were within two miles of the towers Sunday, fire officials said.

For the third straight day, humidity was very low and temperatures were expected in the high 90s. Some 2,000 firefighters were battling the blaze.

Mandatory evacuations were also in effect for neighborhoods in Altadena and for the communities of Acton, La Canada Flintridge, La Crescenta and Big Tujunga Canyon.

There was some progress Sunday, as a small number of La Canada Flintridge residents living west of the Arroyo Seco were told they could go back to their homes.

But more evacuations were ordered in the small town of Acton in the Antelope Valley, and school districts in La Canada Flintridge and Glendale announced that classes were canceled Monday because of the fire.

The fire traveled six to eight miles overnight, burning as actively after dark as it did during the day, said Forest Service Capt. Mike Dietrich. Dietrich said he had never seen a fire grow so quickly without powerful Santa Ana winds to push it.

"The leading edge, the one they're really focused on, is that northern edge. It's moving pretty fast up in that direction," said U.S. Forest Service spokeswoman Randi Jorgenson. "But the fire's growing in all directions. All fronts are going to be areas of concern today."

Fixed-wing aircraft and a DC-10 jumbo jet were dropping water and flame retardant on the fire.

At the fire command post, Schwarzenegger praised firefighters for successfully protecting subdivisions in the foothills.

Rob Driscoll and his wife, Beth Halaas, said they lost their house in Big Tujunga Canyon. By Sunday morning they were desperate for more information and came to the command post to get answers.

"Our neighbors sent us photos of all the other houses that are lost," Halaas said, her voice breaking as her young son nestled his sunburned face in her arms. "We've heard as many as 30 houses burned."

Driscoll said 15 of his neighbors who live on private property within the forest were still waiting for word on their homes. Fire officials assured them teams were working to survey the damage.

At least 12 evacuation centers were set up at schools and community centers in the area.

The center at Crescenta Valley High School filled up after evacuation orders came down at about 2 a.m., but by Sunday afternoon fewer than two dozen people remained. Residents trickled in to get information and snacks.

Debbie and Mercer Barrows said their house was saved but they lost their scenic view of a hillside to the flames.

"That'll grow back," said Mercer Barrows, a TV producer.

The Barrows didn't consider staying in their home because there's only one way in to their La Crescenta neighborhood.

"It depends where your house is, if you can see what's coming. If you're up next to steep and heavy brush like we are, forget it," Barrows said.

The fire, which broke out Wednesday afternoon, was the largest and most dangerous of several burning around southern and central California and in Yosemite National Park.

A second fire in the Angeles National Forest was burning several miles to the east in a canyon above the city of Azusa. The 3.4-square-mile blaze, which started Tuesday afternoon, was 95 percent contained Sunday. No homes were threatened, and full containment was expected by Monday.

A wildfire on the Palos Verdes Peninsula on the south Los Angeles County coast was 100 percent contained, according to county fire officials.

Southeast of Los Angeles in Riverside County, a 3.8-square-mile fire in a rural area of the San Bernardino National Forest was 75 percent contained as it burned in steep, rocky terrain in Beeb Canyon. No structures were threatened.

To the north, in the state's coastal midsection, all evacuation orders were lifted Sunday after a 10-square-mile fire burned near the Monterey County town of Soledad. The blaze, 80 percent contained, was started by agricultural fireworks used to scare animals away from crops. The fire destroyed one home.

In Mariposa County, a nearly 7-square-mile fire burned in Yosemite National Park. The blaze was 50 percent contained Sunday, said park spokeswoman Vickie Mates. Two people sustained minor injuries, she said.

Park officials closed a campground and a portion of Highway 120, anticipating that the fire would spread north toward Tioga Road, the highest elevation route through the Sierra.

About 50 homes in the towns of El Portal and Foresta were under evacuation orders and roads in the area will remain closed through Monday, Mates said.