The Apple Fire burning in the San Bernardino National Forest was 90% contained Saturday morning after charring 33,424 acres.
Command of the firefighting efforts was transferred Friday from the federal government's California Incident Management Team 2 to the San Bernardino National Forest, which is in unified command with Cal Fire, according to Zach Behrens, a national forest spokesman.
But fire officials warned that despite progress being made against the blaze, more work was needed before it was fully extinguished.
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"The work is not over," according to a U.S. Forest Service statement. "Suppression repair efforts will continue over the coming weeks. Crews will remain to mop up along the fireline and repair impacts on the landscape. Expect heavy equipment in areas that are being rehabilitated."
Full containment was expected by Monday, the Forest Service said.
Since sparking July 31 in Cherry Valley due to a diesel vehicle malfunction, the Apple Fire has injured four firefighters and destroyed four homes and eight outbuildings. An estimated 2,600 residences and 7,800 people were evacuated at the height of the blaze.
As of Friday, 897 fire personnel remained on scene, who were being aided by nine water-dropping helicopters. All Cal Fire air tankers have departed.
Officials are expecting wind gusts of up to 25 mph and increasing temperatures through the weekend, but said fire lines passed the test of winds earlier in the week.
With fire lines holding, the Forest Service has begun assessing the severity of the damage caused by the fire in the San Bernardino National Forest earlier this week, looking into the variety of environmental impacts caused by the fire, including watershed damage that could spur dangerous flood conditions during the Southern California wet season, officials said.
The blaze burned through federal, state and private lands, according to Cathleen Thompson of the U.S. Department of Agriculture, and several governmental agencies will have to conduct their own post-fire assessments as the forest service is doing in the national forest.
The Apple Fire also burned through the Morongo Band of Mission Indians reservation, and the damage to the reservation will be assessed by the U.S. Department of Interior.
"Tribal lands are considered federal land as they are managed jointly by the tribes and the Bureau of Indian Affairs," Thompson said.
The Bureau of Indian Affairs falls under the U.S. Department of Interior.
The American Red Cross announced Tuesday afternoon that all relief operations within the fire zone, including maintenance of services at a temporary evacuation center that had been established at Beaumont High School, were finished because all evacuation orders have been lifted.
The nonprofit organization said it helped 183 people affected by the Apple Fire, served at least 2,196 meals and snacks, and provided more than 300 overnight hotel stays for evacuees.
The San Gorgonio Wilderness area -- where 7,249 acres have burned due to the Apple Fire -- remains closed to the public.