At least 17 people in Oregon, California and Washington have now died because of the devastating wildfires ravaging the West Coast, and the destruction is anticipated to worsen, according to Oregon Gov. Kate Brown.
There were dozens of active fires, with nearly 900,000 acres burned in the state as of early Thursday afternoon, according to the Oregon Office of Emergency Management. Those wildfires have scorched about 500 square miles since Monday.
Tens of thousands of residents have been evacuated, and the fires have destroyed thousands of structures, according to authorities.
"Over the last 24 hours, Oregon has experienced unprecedented fires, with devastating consequences across the state," Brown said in a statement Thursday. "Our number-one priority right now is saving lives. This could be the greatest loss of human lives and property due to wildfires in our state's history."
The death toll rose sharply on Thursday evening as the Butte County, California, sheriff announced seven more deaths from the North Complex Fire -- formerly known as the Bear Fire. There was also an additional death reported from the Slater Fire in Siskiyou County, California.
Butte County Sheriff Kory Honea also said 16 people remain unaccounted for.
So far at least four deaths have been reported in Oregon -- two in Marion County in the Santiam Fire and two in the town of Medford in the Almeda Fire.
The Almeda Fire, in Jackson County in the southern part of the state, has devastated the towns of Phoenix and Talent, where hundreds of homes and businesses are destroyed. The Jackson County Sheriff's Office said more deaths are expected.
Jackson County Sheriff Nate Sickler said a criminal investigation has been launched to determine the origin point of the Almeda Fire, where human remains were found.
Many of the fires in Oregon are still 0% contained, including the Beachie Creek and Riverside fires, which have burned more than 182,000 and 112,000 acres, respectively.
Other major fires include the Lionhead Fire, which is more than 109,000 acres and is 5% contained, and the Archie Creek Fire that has burned 68,000 acres and is only 1% contained.
In Clackamas County, Oregon, four fires have forced thousands to evacuate. The blazes there have destroyed 230 structures, including at least 16 homes, with another 600 threatened. The entire county is under some type of evacuation order.
The destruction has led Oregon lawmakers to plead with President Donald Trump to approve emergency disaster funding to aid the state's battle with the wildfires.
"It is imperative that the federal government support these local communities with the resources they need. ... Given the severity and speed with which these fires are spreading across my district, I urge you to expedite the declaration process to ensure that Oregonians have the resources they need to respond to and recover quickly from these devastating wildfires," Rep. Peter DeFazio, along with other Oregon lawmakers, wrote in a letter to Trump.
His thoughts were echoed by Sen. Jeff Merkley.
"The number and scale of fires burning in Oregon is unprecedented, and Oregonians who are suffering need immediate relief," the senator tweeted. "I'm leading the congressional delegation in pushing for the federal assistance that we need to manage and recover from this crisis."
Air quality alerts remain in effect from Washington to central California due to all the smoke from the wildfires.
South of Oregon, the Golden State's sky is eerily orange and red as fire personnel battle more than two dozen massive blazes.
Cal Fire said Thursday evening that 2.6 million acres have burned across the state currently.
The North Complex Fire -- a joining of the previously named Bear Fire and Claremont Fire -- had grown to over 247,000 acres with zero percent containment Thursday evening, according to Cal Fire.
Thirty-seven fires had emerged since Wednesday alone and more than 14,000 firefighters are engaged across the state.
The Creek Fire in Fresno County has consumed more than 175,000 acres and is still 0% contained. It's forced more than 45,000 people to evacuate and has destroyed at least 365 structures, including 60 residences.
Elsewhere in California, the Slater Fire has destroyed more than 150 homes and caused at least two deaths. It is currently 120,000 acres. The Valley Fire is over 17,000 acres and about 35% contained.
Six of the top 20 largest wildfires in California history have occurred this year.
California Gov. Gavin Newsom said the viral images of an orange sky in San Francisco and other parts of the state are a "cry out for change." He said to help prevent future wildfires all levels of government must step up to fight climate change.
"CA has invested more in wildfire prevention than any time in our history. Enacted bold climate policies. But it's not enough," the governor tweeted. "We must do more. We need action at EVERY level. CA cannot do this alone. Climate change is REAL. So please — VOTE."
ABC News' Jenna Harrison and Marilyn Heck contributed to this report.