In this photo provided by the Bootleg Fire Incident Command, the Bootleg Fire burns at night near Highway 34 in southern Oregon on Thursday, July 15, 2021. (Photo: AP)

SAN FRANCISCO, July 18 (Xinhua) -- The Bootleg fire in the U.S. State of Oregon burned 298,662 acres (about 1,209 square km) as of Sunday morning, fire officials said.

The largest wildfire in the state was 22 percent contained from 7 percent containment since Friday.

The fire, which was growing to the east, started July 6 northeast of Klamath Falls and threatened more than 5,000 structures, according to fire officials.

This came after the National Weather Service issued a "red flag warning" Friday afternoon for the Klamath Basin and Fremont-Winema National Forest, which indicates critical fire weather conditions or weather conditions that may cause fires, according to a report by the OregonLive.