A view of homes that were destroyed by the Carr Fire on July 27, 2018 in Redding, California. A Redding firefighter and bulldozer operator were killed battling the fast moving Carr Fire that has burned over 126,000 acres and destroyed more than 1,000 homes.

Seventeen people were missing on Saturday as a monster wildfire in Northern California spread after killing two firefighters, destroying hundreds of buildings and sending tens of thousands of frantic residents fleeing from their homes.

More than 38,000 people in Redding and elsewhere in Shasta County have been ordered to leave their homes from the 80,900-acre (32,740-hectare) Carr Fire, which has destroyed at least 500 homes and businesses. Officials warned further evacuation orders were possible. Some 3,400 firefighters on the ground and in 17 helicopters were battling the fire, which was just 5 percent contained as it ripped through Redding, a city of 90,000 people, in California's scenic Shasta-Trinity area. It has left Keswick, a town of 450, in smoldering ruins, the California Department of Forestry and Fire Protection said. Another 5,000 buildings are threatened, Cal Fire said.

Law enforcement officials are currently trying to locate 17 people reported missing, but noted that the number of missing has fluctuated in recent days as new people are reported missing and others located, Redding Police Sergeant Todd Cogle said by telephone.

"We don't want to give the impression that all these people have suffered some kind of grave circumstances," Cogle said. "We sent officers to some of these places (where they lived) and the houses were intact, so it's more than likely those people just evacuated." There are currently 89 large wildfires blazing across 14 U.S. states, mostly in the West, according to the National Interagency Fire Center. So far this year, wildfires have scorched almost 4.3 million acres (1.7 million hectares) across the United States, above the 3.7 million-acre (1.5 million-hectare) average for the same period over the last decade.