The 20-acre blaze broke out around 10 p.m. and was moving at a moderate speed, according to authorities. It started along the freeway north of the Kenwood Avenue off-ramp.
By midnight, firefighters were able to reach 25 percent containment and reopened some lanes on the 15 Freeway.
Multiple agencies were working to knock down the fire.
Authorities said the fire was around the same area as the devastating Blue Cut Fire that charred thousands of acres and prompted thousands of evacuations.