The brush fire is 5 percent contained and was first reported in the area of Highway 330 near Forest Road, according to San Bernardino National Forest officials on Twitter.
The incident began as a small, 1-acre fire before quickly increasing to at least 25 acres in less than an hour.
Acreage estimate has been increased to 3 acres. pic.twitter.com/Q0C7EZZhET— San Bernardino National Forest (@SanBernardinoNF) June 30, 2018
San Bernardino County and Cal Fire firefighters were assisting forest officials in the firefight with resources from the ground and air.
There have been no reports of injuries or threatened structures.