By Sharon Bernstein

GROVELAND Calif. (Reuters) - Firefighters gained ground on Tuesday against a blaze burning on the western edge of Yosemite National Park and an adjacent national forest, where flames have forced the evacuation of several dozen homes and the closure of three campgrounds.

The El Portal fire has scorched more than 3,000 acres since it erupted on Saturday, destroying a duplex home and threatening dozens of other dwellings around the western park boundary, a spokesman for the federal fire command said.

By Tuesday morning, a firefighting force of some 640 personnel had managed to carve containment lines through brush and timber around nearly 20 percent of the blaze's perimeter, up from a containment level of 5 percent reported a day earlier.

Residents forced to flee from the tiny community of Old El Portal were permitted to return early on Tuesday, but 45 homes in the neighboring enclave of Foresta, just inside the park, remained under evacuation orders, the spokesman said.

A stretch of Big Oak Flat Road inside the park also was closed due to the fire, along with Crane Flat, Yosemite Creek and Bridalveil Creek campgrounds. Bridalveil Creek was being used as a camp for firefighters.

The rest of the park remained opened to visitors, including Tioga Pass Road, Highway 41 and Highway 140. Two firefighters have suffered minor injuries, according to the spokesman.

The blaze was burning in a corner of Yosemite and the Stanislaus National Forest south of the 250,000-plus acres blackened last summer by the so-called Rim Fire, which ranks as the third-largest California wildfire on record.

About 180 miles northwest of the El Portal blaze, fire crews have encircled about 80 percent of a wildfire that has destroyed 13 homes and devoured some 3,800 acres in the drought-parched Sierra foothills east of Sacramento, according to the California Department of Forestry and Fire Protection.

The latest progress against that blaze, dubbed the Sand Fire, came after authorities reported that aerial firefighting efforts had been disrupted briefly by a small drone aircraft operated in the area by a private hobbyist seeking to film the fire.

California is in the midst of one of its most severe droughts on record, a factor that fire officials say has contributed to the growing number and intensity of wildfires across the state this year.


(Additional reporting and writing by Steve Gorman in Los Angeles; Editing by Will Dunham)