The Post Fire in Los Angeles County has consumed more than 15,000 acres

A fire in Los Angeles County that forced the evacuations of hundreds of people from a state park has burned more than 15,000 acres since it started Saturday, authorities said.

The Post Fire had burned 15,611 acres and was 20% contained as of Monday evening, according to the California Department of Forestry and Fire Protection, also known as Cal Fire.

More than 1,000 firefighters were on scene, with more on their way, Los Angeles County Fire Department Section Chief Kenichi Ballew-Haskett told CNN Monday morning.

“We’re getting people on notice that if we have to issue a mandatory evacuation order that they need to leave,” Ballew-Haskett said, advising people residents to have their bags packed, a full tank of gas and cell phones ready. “Once the sheriffs come by or law enforcement asks you to leave, it means the danger is imminent.”

The wildfire began Saturday afternoon in Gorman, an unincorporated community in northwestern Los Angeles County. The cause of the blaze is still under investigation, according to Cal Fire.

California State Park Services evacuated 1,200 people from Hungry Valley Park, Cal Fire said. The fire had destroyed one commercial property by Monday evening, according to the Los Angeles County Fire Department.

Evacuation orders are in place for areas west of Interstate 5 between Pyramid Lake and Gorman, and evacuation warnings are in place for areas south of Pyramid Lake between Old Ridge Route and the Los Angeles County line. Additional evacuation orders were issued Monday afternoon for the area south of Pyramid Lake, west of I-5, east of the County line and just north of the Templin Highway, the Los Angeles County Sheriff’s Department said.

As of Monday afternoon, the blaze was not spreading outside its current perimeter, but crews are still concerned about high winds that are supposed to continue through Tuesday afternoon, Fire Public Information Officer Flemming Bertelsen with the Los Padres National Forest told CNN.

Crews have been maintaining the perimeter of the fire by patrolling the line and looking for spot fires, Bertelsen said.

“The fire is not spreading in any significant manner right now, our lines are holding, but we have like 24 hours more of this wind,” Bertelsen said, adding winds have been reaching 50 to 60 mph at the ridge tops. Low humidity is also a major concern, he said.

“We are going to be tested, especially tonight,” he said. The most active part of the fire is close to Piru Creek – and if it crosses the creek, the wildfire will enter heavy mountain terrain, he said.

The National Weather Service in Los Angeles warned Sunday of wind gusts up to 60 to 70 mph, creating conditions that could potentially fuel the flames. A red flag warning was issued for the I-5 corridor in Los Angeles County and the Ventura County mountains until 5 p.m. Monday.

Two adults and a child were taken to a hospital with minor injuries, CNN affiliate KABC reported, citing a spokesperson for the Los Angeles County Fire Department.

Crews are working to contain the fire and “aircraft are working to stop forward progress but have limited visibility,” according to the fire department.

Pyramid Lake is also closed because of the threat posed by the fire, the fire department said.

Meanwhile in Northern California, the Point Fire had burned about 1,190 acres in Sonoma County and destroyed at least two structures as of Monday evening, according to Cal Fire.

Evacuation orders were issued Sunday for some residents, with first responders going door to door to assist, the Sonoma County Sheriff’s Office said.

Officials have deployed 36 fire engines, three helicopters, seven dozers, six hand crews and three water tenders to fight the fire, which was about 20% contained by Monday evening, Cal Fire reported.

Another wildfire, the Aero Fire, started southeast of Sacramento Monday afternoon and grew with dangerous speed, consuming over 900 acres within just an hour and a half, Cal Fire said in a post on Facebook. By Monday evening, it had grown to 1,500 acres. Strong winds are impacting firefighters’ ability to establish a containment line, the post added.

Evacuation orders and warnings were in place, according to the post, but aerials from CNN affiliate KCRA show the area is not densely populated. It’s not immediately clear how many structures are threatened in the area.

Further north, the Sites Fire in Colusa County had burned more than 4,400 acres and had no containment as of Monday evening, according to Cal Fire.

CNN’s Camila Bernal, Sarah Moon, and Taylor Romine contributed to this report.

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