The Gifford fire, which has been fueled by dry conditions and warm weather, has spread to two counties, officials said.
The Gifford fire, which has been fueled by dry conditions and warm weather, erupted on Saturday into a 23,000-acre blaze within the Los Padres National Forest in south-central California after several small fires merged into one large wildfire, officials said.
Firefighters have been battling the blaze affecting Santa Barbara and San Luis Obispo Counties since Friday but have not been able to contain it, according to fire officials.
The wildfire is primarily burning vegetation and has had multiple ignition points along Highway 166, a road that cuts across the forest and is about 20 miles northeast of the city of Santa Maria near the central coast, said Andrew Madsen, a spokesman for the Los Padres National Forest.
A spokesman for the U.S. Forest Service confirmed that a series of small fires began along a stretch of Highway 166, a corridor known for fires linked to vehicular traffic. Those individual fires combined into one large wildfire as of Saturday.
According to fire officials, about 60 to 70 people who live in ranches along the highway have been evacuated.
The Gifford fire had grown to 23,000 acres and remained only 5 percent contained as of Saturday, the authorities said.
The fire continued to spread aggressively because it was being fueled by dry conditions and warm weather, they said. The cause of the fire remained under investigation.
Ground crews and aircraft were being used to suppress the fire, according to an update issued on Friday afternoon by Cal Fire, the state's fire protection agency. Additional resources have been ordered as officials work to get ahead of the blaze.
One person sustained serious burn injuries and was transported to a hospital in Santa Maria for treatment, a park official said.
The fire is burning in a rural, sparsely populated agricultural area, according to park officials.
Officials said the fire posed a risk to commercial infrastructure and some residences in the nearby communities of Cuyama and New Cuyama in the Cuyama valley of Santa Barbara County, a park official said.
If the fire continues moving east, it could enter the recently burned terrain of the Madre fire, which scorched more than 80,000 acres in San Luis Obispo County and was declared out just last weekend, the authorities said.
The biggest population center, with about 600 people, is approximately 20 miles east of the fire zone, in the rural communities of Cuyama and New Cuyama. The area is currently not under threat.
Orlando Mayorquín and Amy Graff contributed reporting. Susan C. Beachy contributed research.