The United States on Monday was managing 94 large wildfires that have burned 843,124 hectares, the National Interagency Fire Center said.

More than 27,000 firefighters and support personnel have been deployed to combat the fires nationwide, the fire center said.

In addition to California, where the largest fires raged, the center reported that fuel and fire advisories have been issued for Oregon, Washington, Nevada, Idaho and Utah.

The White House on Monday posted a statement on X about its response to the fires:

“Our administration has mobilized resources to support fire suppression efforts as firefighters battle wildfires in California and across the Pacific Northwest. We’re grateful to the firefighters and first responders on the front lines, and urge everyone in the affected areas to remain vigilant and listen to local officials.”

The Park Fire in California, burning through several counties, was the largest wildfire in the country. It was also the sixth largest in Califorina's history.

The California Department of Forestry and Fire Protection, known as Cal Fire, said early Monday that the Park Fire “stayed active well into the night,” but that by early morning, “an increase in humidity caused the fire activity to moderate.”

However, the Park Fire was expected to re-energize later Monday, according to Cal Fire, because of a combination of southwest winds, low fuel moisture and fire-receptive fuels.

By Monday morning, the Park Fire had engulfed nearly 150,000 hectares, an area larger than the city of Los Angeles.

Cal Fire wrote Monday on X, “Staying prepared is crucial. ... Have your go bag packed and know two evacuation routes.”

A man accused of setting the fire was arrested Thursday. Ronnie Dean Stout II was detained on suspicion of arson after allegedly pushing a burning car into a gully near the northern California city of Chico, according to Butte County District Attorney Mike Ramsey.

In Oregon, the National Guard has been deployed to fight fires in the east of the state.

“The wildfire situation on the ground is dynamic and challenging, and we need all hands on deck,” Governor Tina Kotek said. One of the fires — the Durkee Fire — has scorched 116,800 hectares and has been 49% contained.

Utah Fire Info said Monday that 88 new fires have started in Utah since July 21, with 44% of them determined to have been caused by people.

The Federal Emergency Management Agency (FEMA) defines a wildfire as an “unplanned, unwanted fire burning in a natural area, such as a forest, grassland or prairie.”

Wildfires can start from natural causes, but most are caused by humans, accidentally or intentionally, according to FEMA.