SAN BERNARDINO, Calif. (AP) — A wildfire the erupted near a busy Southern California freeway prompted the evacuation of 30 rural homes Tuesday afternoon as firefighters attacked it hard from the air.

Helicopters and a DC-10 made massive water drops on the brushy foothills of the San Bernardino Mountains and by early evening had reduced much of the blaze to white smoke.

"They hit it pretty hard and heavy," said CarolUnderhill, a San Bernardino Mountains spokeswoman.

There was no immediate word, however, on when the blaze might be contained and the evacuation lifted.

The fire was reported shortly before near Interstate 15 in the CajonPass, a heavily traveled truck route east of Los Angeles. It was burning at the base of the pass in the Sycamore Flats area.

Winds gusting to 18 mph pushed the flames and at least 100 firefighters fought the blaze, Underhill said.

Meanwhile, a 250-acre wildfire in the San Gabriel Mountains east of Los Angeles was 70 percent contained and crews needed to cut only a few miles of fireline to completely surround it, said Nathan Judy, a spokesman with the U.S. Fire Service.

Winds were light and the fire barely moved through the day, instead snapping up leftover brush inside the scorched area.

"There isn't even any active flame. We're not seeing any smoke. We're seeing small pockets of flame here and there," Judy said.

The nearest towns were miles away, and by early afternoon no homes were threatened, Judy said.

At the fire's height, about 450 firefighters were aided by aircraft, which included drops by Super Scoopers and heavy helicopters. One firefighter was treated for a minor leg injury, Judy said.

High temperatures in the region were in the 80s, but Judy said they were cooling down. Forecasters said an upper-level, low pressure area moving into the Pacific Northwest on Tuesday night and Wednesday would cause an increasing flow of cool, moist air from the ocean onto the land.

The fire was burning in terrain east of the 250-square-mile area of the AngelesNational Forest that was devastated by the 2009 Station Fire.