SACRAMENTO, Calif. — California firefighters expected to gain ground Sunday on a wind-driven wildfire that scorched thousands of acres 60 miles (97 kilometers) east of San Francisco, burned down a home and forced residents to flee the area near the central California city of Tracy. The fire erupted Saturday afternoon in the grassy hills managed by the Lawrence Livermore National Laboratory, one of the country’s key centers for nuclear weapons science and technology. The cause was under investigation. The California Department of Forestry and Fire Protection said the research center was not under immediate threat from the blaze, dubbed the Corral Fire, which had devoured some 20 square miles (52 square kilometers) by Sunday afternoon and was 30% contained. Thousands of people in the area, including parts of the city of Tracy with a population of 100,000, were ordered to leave for evacuation centers.

Additional coverage in ABC News: 2 firefighters injured as wildfire spreads to 14,000 acres near San Francisco