An inferno scorching swathes of southern California threatened the homes of more than 82,000 people Wednesday, sending flaming "firenadoes" tearing across the brush and prompting a state of emergency.

More than 1,300 firefighters were battling the giant blaze, with more on the way, but they were unable to contain the blaze on Wednesday.

Dramatic local TV news footage of the wildfire captured from the front line in the town of Phelan showed tornado-like flaming vortexes -- known as "firenadoes" -- sent spinning into the air by the unusual ferocity of the blaze.

"We have very, very dry brush, thick fuel, it helps move it along very quickly," Lynne Tolmachoff, spokeswoman for the state firefighting agency Cal Fire, told AFP.

"It is very dangerous to the public and also to the firefighters."

Governor Jerry Brown declared a state of emergency for San Bernardino County, just 60 miles (100 kilometers) east of Los Angeles, where the so-called Bluecut Fire was quickly growing, its cause still unclear.

The inferno began around 10:30 am (1730 GMT) Tuesday and has already burned through 30,000 acres (more than 12,000 hectares), according to the multi-agency Inciweb information site.

More than 34,500 homes were threatened and 82,640 people were under evacuation warnings.

"There is imminent threat to public safety, rail traffic and structures in the Cajon Pass, Lytle Creek, Wrightwood, Oak Hills and surrounding areas," Inciweb said.

From the highway between Wrightwood and Lytle Creek, a thick cloud of smoke could be seen blanketing the entire valley.

- 'Not worth your life' -

A dozen fire trucks awaited orders to evacuate Paso Lane, located between several hills that were being devoured by flames, columns of smoke billowing into the sky.

"The whole community is being evacuated," said local firefighter Mike Anderson, who had been battling the blaze with his team for more than 24 straight hours.

"The fire is moving very fast straight through Highway 138, it is still growing."

Chon Bribiescas of the US Forest Services said later that the evacuation area was being expanded, with the wind picking up and the temperature soaring to 100 degrees Fahrenheit (38 Celsius).

"The fire is consuming 100 acres in a few minutes instead of 100 per hour," she told AFP, adding that many residents had decided against the best advice to remain in their homes.

"In California, we cannot force people from their homes, but that means we have firefighters that have to come back to the mandatory evacuation zones instead of fighting the fire.

"I try to tell people that there is nothing in your home that is worth your life."

At a gas station in the outpost of Pinon Hills, 10 miles northwest of the fire, Jeannine Yglesia was buying ice with her 24-year-old son.

"I have 17 to 18 people staying at my house now, friends and their families that have had to evacuate from Wrightwood," she said.

Gail Nieto, a 65-year-old woman buying groceries, was forced to flee Wrightwood on Tuesday night.

"It's the fourth time in 30 years, but it's the fastest-growing fire I have ever seen," she said, trembling.

- Perfect conditions -

Among equipment already deployed were 152 fire engines, eight air tankers plus two Very Large Air Tankers (VLATs), and eight helicopters, including night-flying helicopters.

The inferno has claimed one high-profile victim so far: the Summit Inn, an old-fashioned diner on the world-famous Route 66 that counted celebrities Elvis Presley and Clint Eastwood among its clientele.

Several roads were closed while two firefighters were injured after they were surrounded by flames. They were treated at a hospital and sent back out to fight the blaze, Inciweb said.

Elaine Bowder, 75, another resident living in the inferno's path, said she may lose her new house.

"We have our important things and we are insured," she said. "But we had to leave one of our cats at home."

"I'm very upset, I'm very attached to her," she added, breaking down in tears.

Colette Martinez, whose friends had offered her somewhere to stay, said she left her home with only what she needed. "The material things don't matter. You can always get those back."

California is in its fifth year of a record drought, with parts experiencing a heat wave and strong seasonal gusts known as the Santa Ana winds, a recipe for perfect wildfire conditions.

Thousands of firefighters are already committed to several other major fires -- north of San Francisco, in central California's wine region and in the scenic coastal area of Big Sur.