Flames illuminate the smoke rising from the Beckwourth complex fire. (Ty ONeil/Getty)
"A damage assessment team has arrived to validate and assess reports of structures damaged or destroyed," a forest statement said.
In Oregon, the Bootleg Fire covered 621 square kilometres in the Fremont-Winema National Forest, near the Klamath County town of Sprague River.
After doubling in size at least twice over the weekend, it grew only incrementally on Sunday, a sign of some progress, said Rich Saalsaa, spokesman for the Oregon State Fire Marshall.
"It's allowed firefighters to build more lines and go on the offensive," Mr Saalsaa said.