The Oso Complex Fire started June 20, 1998 and burned 5,185 acres (21 km²) in the Santa Fe National Forest in the Jemez Mountains, including more than 1,200 acres (4.9 km²) of Santa Clara Pueblo land. The fire came within 8 miles (13 km) of Los Alamos, New Mexico and was contained by July 6, 1998, aided by rain. The cause of the fire was determined to be arson.