The so-called South Fire was reported shortly shortly after 1:30 p.m. and was burning amid light winds in an area west of the interstate and south of Lytle Creek Road. Hours later, the containment level remained at 0%, but crews appeared to have gotten the upper hand by nightfall.
Several structures and parked vehicles were engulfed in flames, and residents were seen trying to rescue llamas and horses who were penned inside enclosed areas on ranch-like properties. Propane tanks were heard exploding.
Firefighters on the ground raced to douse flames and protect other homes as at least two tankers dropped water and Phos-Chek from overhead. At least four homes and numerous outbuildings were destroyed as 1,000 residents were under evacuation.
Lytle Creek: 500-acre blaze burns at least 2 structures, prompts evacuation of homes
Lanes remained open in both directions on the 15 Freeway just south of the Cajon Pass, but traffic was slowing to a standstill amid smoky conditions. Northbound and southbound ramps were closed at Sierra Avenue, Caltrans said.
There were no immediate reports of injuries.
The San Bernardino County Fire Department initially said the blaze began when an excavator that was being operated in a backyard struck a rock, igniting sparks that spread to dry brush nearby. A fire department spokesperson later said there was no definite cause and an investigation is ongoing.
Cal Fire and San Bernardino National Forest firefighters also responded to the burn area. More than 100 personnel were involved in the firefight.
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At least two residents in the area ignored a subsequent evacuation order, then later called 911 when their home was surrounded by flames, fire officials said. Firefighters returned and were able to rescue the trapped residents.
One resident said sprinklers installed on the roof of his home helped save the property from being destroyed.
South Fire: Man says sprinklers on home's roof helped beat back flames
South Fire: Man says sprinklers on home's roof helped beat back flames
An evacuation order was issued for Lytle Creek Road south of the Lytle Creek ranger station, west of Sierra Avenue, north of the 15 Freeway and east of Duncan Canyon to the foothills, the San Bernardino County Sheriff's Department.
Residents in all areas north of the ranger station were initially ordered to shelter in place, but an evacuation order was later issued.
An evacuation warning was issued for the area north of Glen Helen Parkway, east of Sierra Avenue and Lytle Creek Rd. west of the 15 Freeway.
An evacuation center for large animals was established at the Devore Animal Shelter, located at 19777 Shelter Way in San Bernardino.
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