The gigantic wildfire in northern California continued to spread Friday, as state authorities warned that increased fire activity was likely later in the day. Meanwhile, thousands of firefighters were still working to combat this blaze and several other major wildfires that have destroyed hundreds of structures and are threatening scores of other buildings across the state.

Nearly a week after the King fire began burning in El Dorado County, it had grown to cover more than 76,000 acres by Friday morning, according to the California Department of Forestry and Fire Protection (known as Cal Fire). That means the King fire, the largest in the state right now, is covering more than 119 square miles, an area nearly as large as the entire city of Portland.

On Friday afternoon, officials confirmed that the King fire had damaged or destroyed some structures. But they were not immediately able to say what kind of buildings they were or how many were impacted.

Already, the King fire has forced about 2,800 people to evacuate the area since it began Saturday, and about 12,000 residences are still threatened, officials said.

The weather on Friday is expected to facilitate the fire’s continued spread. A combination of strong winds, higher temperatures and decreased humidity could lead to more fire activity, Cal Fire said in a statement Friday morning.

Police arrested Wayne Allen Huntsman, 37, on Wednesday night and have charged him with purposefully setting this fire. Vern Pierson, district attorney for El Dorado County, said few details could be offered regarding the arrest because the investigation was ongoing.

A criminal complaint alleges that Huntsman “willfully and maliciously” set the fire. Pierson said at a news conference Thursday that police do not believe anyone else was involved, and Huntsman’s bail was set at $10 million.

Huntsman’s sister told the Associated Press she did not think her brother would intentionally set the fire, saying that he has always been careful with campfires.

“He’s a really good guy,” Tami Criswell said. “He would never do anything intentionally to hurt anybody.”

Gov. Jerry Brown declared a state of emergency in El Dorado and Siskiyou counties on Wednesday due to the effects of two of the fires, which he said threatened power lines, water storage tanks and other infrastructure.

There are currently nine major wildfires in the state, Cal Fire is reporting. As a result, more than 7,600 firefighters have been deployed to fight the fires, with most of them responding to the growing King blaze.

Another wildfire — known as the Boles fire in Siskiyou County — had burned across more than 470 acres since starting on Monday. It was about 90 percent contained by Friday.

Related: Head to In Sight for more remarkable images of the King fire.

This post has been updated. Last update: 4:32 p.m.