LOS ANGELES, Sept. 6 -- At least a quarter of the Angeles National Forest will be closed indefinitely to assess the devastation of California's Station Fire, officials said.

The fire has burned through 242 square miles, destroyed 76 homes and claimed the lives of two firefighters. It is the 10th largest fire in California's modern history and the largest in Los Angeles County in modern history.

The blaze was 51 percent contained Sunday and burning eastward into the San Gabriel Wilderness Area, less than 25 miles from downtown Los Angeles, U.S. Forest Service spokesman Stanton Florea told the Los Angeles Times.

A large part of the Angeles National Forest and the Angeles Crest Highway are to be closed so officials can assess the likelihood of floods and debris during winter rains and the danger from rocks unmoored by the loss of vegetation, Florea said. The fire jumped a firebreak along the Angeles Crest Highway.

The fire raged through the forest, destroying trails, campgrounds, picnic areas and swimming holes popular with Southern Californians.

"This is the playground of LA" Florea said. "More than 70 percent of the open space in LA County is in the Angeles National Forest