California Wildfire Engulfs Freeway as Drones Delay Response Efforts

A wildfire that broke out northeast of Los Angeles jumped from the arid San Bernardino mountains on to Interstate 15, torching at least 20 cars that were stuck in Friday afternoon traffic on the Cajon Pass.

"People were screaming — it was just crazy," said Russell Allevato, who watched as flames engulfed his rental car and destroyed everything inside it while he, his nephew, and his two teenage daughters fled to safety.

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"We were surrounded by the flames," he said by phone from while in a California Highway Patrol vehicle. "They were to the left, then in front of us, and they came around to the right. We were in a big horseshoe in the middle."

According to the US Forest Service, two semi-trucks were among the vehicles destroyed by the fire, and 10 cars were damaged by the flames. Four buildings were also destroyed in the fire. No injuries have yet been reported.

— NBC Los Angeles (@NBCLA)July 17, 2015

Investigators have not determined the cause of the wildfire, but they believe it broke out at about 2:30pm Friday afternoon near the unincorporated community of Baldy Mesa in San Bernardino County.

"We had some highway patrolmen who said they had never seen fire travel that fast," said Greg Kieran, a San Bernardino County Fire Hazmat specialist. "It just overran these people before they even knew what hit them."

One-thousand firefighters from Calfire, San Bernardino County Fire, and the San Bernardino County Sheriff's office were deployed to fight the flames, along with 22 fire trucks and other equipment. Six fixed-wing tanker planes also dispatched to help fight the blaze, though at one point, according to the Forest Service, the tankers had to be halted for at least 25 minutes because at least one drone was operating in the area. It's still unclear what the drone was doing near the fire.

Here's the moment the burning semi truck burst into a fire ball. — Jim Dalrymple II (@JimDalrympleII)July 18, 2015

Local authorities ordered mandatory evacuations of the area on Friday, where last night more than 3,500 acres had already burned. Grass and chaparral, much drier than usual due to California's historic drought, fueled the flames, which were also aided by 40 mph winds.

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The fire was 5 percent contained as of Saturday morning; all northbound lanes of Interstate 15 had been reopened, as well as three southbound lanes.

Authorities hoping to hold the fire line Saturday may be helped by rain carried in by tropical storm Dolores, which is expected to hit Southern California over the weekend. But at the same time, according to the National Weather Service, Dolores will be bringing the threat of "deadly cloud-to-ground-lightning" and more strong, gusty winds.

Follow Tessa Stuart on Twitter: @tessastuart

The Associated Press contributed to this report.