More than 240 firefighters are working to contain a human-caused fire burning approximately 34,000 acres on the Warm Springs Reservation as of Saturday afternoon.
The Nena Springs Fire is burning in dry grass and brush on steep terrain.
Gov. Kate Brown authorized additional resources to help protect homes and structures Friday afternoon.
It has burned historic, unoccupied buildings and is threatening some homes.
Some nearby communities have been ordered to evacuate and leave the area, including the Schoolie Flat, Simnasho and S-300 subdivisions.
Kah-Nee-Ta Resort is under a level one evacuation notice, meaning people there should be prepared to leave if necessary.
"Local firefighters here have described some of the most extreme fire behavior they’ve seen," said Lt. Damon Simmons with the Oregon State Fire Marshal's Incident Management Team.
"Moderate winds, high heat, low humidity, a lot of the same stuff you see in a lot of wildfire, but it’s combining in different ways here because we have a lot of fuel growth," Simmons said.
The Red Cross has opened a shelter at the Warm Springs community center for people who have been displaced by the fire.