CNN  — 

Firefighters in Oregon are racing to slow down two wildfires from merging into a single inferno Friday after blazes in three West Coast states have killed at least 26 people since last month.

Some Oregon communities burned to the ground this week and about 500,000 people have been either ordered to evacuate or warned to be prepared to evacuate. State officials say they are focusing their efforts on saving lives but they anticipate a devastating aftermath.

“We know we are dealing with fire-related deaths, and we are preparing for a mass fatality incident based on what we know and the numbers of structures that have been lost,” Andrew Phelps, director of the Oregon Office of Emergency Management, told reporters Friday.

Oregon Gov. Kate Brown said Friday that wildfires have consumed more than 1 million acres and dozens of people remain missing.

As two major fires in Oregon – the Beachie Creek and Riverside fires – threatened to merge in the coming days, air quality levels have badly deteriorated from smoke. Four of the top five cities worldwide with the worst air pollution are in the region – Portland, Seattle, San Francisco and Vancouver, according to IQAir, a Swiss air quality technology company tracking pollution levels.

The blazes have killed at least six people in Oregon, according to data from the state’s office of emergency management and the Lane County Sheriff’s Office. In California, 19 people have died from mid-August through Friday – including at least nine found dead this week in one Northern California fire – and one person was recently killed in Washington state.

Authorities had said the number of deaths linked to the North Complex Fire were 10 but the Butte County Sheriff Kory Honea said Friday that deputies discovered an anatomical skeleton model made out of resin in a storage shed and believed it was a human body.

When Jim and Tina Weber tried to drive away from a blaze in Oregon’s Blue River area, flames blocked their road, with “fire crossing the road on both sides, and trees falling down,” Jim Weber told CNN affiliate KVAL.

Eventually, firefighters led them and 30 other families to the parking lot of a running track, where they kept spot fires at bay throughout the early hours of Tuesday. Only hours later could firefighters lead them away in a car caravan, he said.

“We went by many, many homes that were still in flames on both sides of the river,” he told KVAL. Much of Blue River, a community of a few hundred people, was destroyed, the governor has said.