The Sanderson Fire was reported about 1 a.m. near La Borde Canyon Road and Jack Rabbit Trail, according to the Riverside County Fire Department.
No injuries or structural damage were reported.
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Shortly before 9 a.m., an evacuation warning was issued for an area that included North Gilman Springs Road and South Timothy Lane, just south of the 60 Freeway. Less than a dozen homes were affected by the warning, officials said.
The evacuation warning was lifted just before 1 p.m.
By 1 p.m., the county fire department said the fire had spread to 1,933 acres as firefighters had stopped the forward progress and reached about 10% containment.
"Firefighters had difficulty accessing the fire due to its location deep into rugged terrain," Cal Fire said in a statement.
At least 130 firefighters were on the scene, the agency said. Helicopters and fixed-wing aircraft were seen dropping water and Phos-Chek on the flames.
The South Coast Air Quality Management District issued a smoke advisory through Monday, saying smoke and ash from the fire will carry into portions of Los Angeles, Orange, Riverside and San Bernardino counties.