A brush fire near a La Verne neighborhood grew from three to 40 acres in just hours Friday afternoon but was 80% contained, authorities said.
Helicopters and ground crews battled the blaze, which was expected to be fully contained late Friday afternoon or evening, said Los Angeles County Fire Department Inspector Keith Mora.
Smoke from the fire was visible from the 210 Freeway as crews worked to keep the flames away from homes.
At one point, television news footage showed flames advancing perilously close to a group of homes situated on the edge of a ravine before water-dropping helicopters doused the fire.
One outhouse was destroyed, Mora said, and no one was injured.