Firefighters continue to battle the largest fire in California history even as another large blaze has been contained.

The Ranch Fire, one of the two wildfires that make up the Mendocino Complex, has burned through 341,047 acres — or 533 square miles — and is at 76 percent containment, Cal Fires reported on Sunday.

Daron Wyatt, a public information officer, said challenging weather conditions and "steep, inaccessible terrain," have made progress against the fire especially difficult, according to The Press Democrat.

The newspaper reported, "Wyatt said he has seen recent photos of some of the 3,500 firefighters assigned to the fire scrambling along hillsides with 60 percent slopes, so steep they needed to pull themselves up by their fire hoses."

By late Sunday the fire had gained another 6,000 acres.

After raging for 17 days, the River Fire was contained on Aug. 13., but not before flames tore through 48,920 acres.

The total acreage consumed by the twin fires is 389,967 since they first broke out on July 27, with a combined containment of 79 percent. In all, 157 homes and some 120 structures have been destroyed.

Matt Burchett, a veteran firefighter and battalion chief with the Draper Fire Department in Utah, was killed in the intense fight against the fire Ranch fire on Aug. 13. The Deseret News reported his body was returned home with a "solemn escort, without lights or sirens" on Friday. He was accompanied by the Utah firefighters who also helped combat the fire.

Despite the difficulties, officials say full containment is still expected by Sept. 1.

Crews continue making progress on the devastating Carr Fire that is raging further north in the Redding area.

Cal Fire reported that the Shasta County fire, set off by sparks from the rim of a flat tire scraping along Highway 299, is now 83 percent contained.

So far, it has charred more than 227,098 acres and is by far the most destructive of the state's fires. It has decimated 1,079 residences, 22 commercial structures and 503 other buildings.

At least seven people have been killed in the fire, started July 23, including three firefighting personnel and a great-grandmother and two children.

It took firefighters a few days longer than they had hoped, but the Ferguson Fire, which shut down swaths of Yosemite National Park and scorched more than 96,000 acres, was fully contained on Saturday night.

Achieving 100 percent containment means officials have stopped it from spreading but it does not mean it is completely out.

As Ferguson Fire Information Officer Brendan Halle told Ryan Levi of the public radio show The California Report,"It's not controlled."

"Controlled would be after there are no more hot spots or smoking areas, and there are still interior pockets of unburned fuel in that containment line that are probably going to smoke for a while until they have the first really good storm or wetting rain up in this region, and that will probably lead to the whole thing being controlled," Halle said.

The Ferguson Fire burned for more than a month — 36 days — killed two firefighters, and has had a calamitous impact on what is traditionally the peak tourist season in and round Yosemite National Park. Levi says that park closures have resulted in about $50 million in lost revenue.

According to Levi, "Park officials closed the popular Yosemite Valley to the public on July 25, and the following week, the fire burned into the park for the first time, leading the National Park Service to close a large portion of the park indefinitely on August 5. Yosemite Valley reopened on August 14. Mariposa Grove and Wawona have also reopened, while Glacier Point remains closed."

The cause of the fire remains under investigation.

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