The so-called Manzanita Fire was reported at around 3:22 p.m. along Highway 330 near Middle Passing Lane, according to the San Bernardino County Fire Department.
Authorities reported seeing smoke and "significant fire running uphill" as crews rushed to the area, according to a California Highway Patrol report log. No injuries or evacuation orders were reported in connection with the fire.
As of 6:40 p.m., authorities reported forward progress of the blaze has stopped after previously reporting "good progress."
Highway 330 was shut down but drivers in the area are still encouraged to use alternate routes.
It's unclear if any homes or structures were threatened.
The cause of the fire is unknown.
This is a developing story. This article will continue to be updated as more information becomes available.