(Update 7:20 p.m.) The Crooked Creek Fire grew to 5,100 acres as of Wednesday evening.
The cause remains unknown, and there is no containment at this point.
(Update: 1:45 p.m.) The Crooked Creek Fire was estimated at 4,500 acres Wednesday afternoon.
The fire is burning along the Carbon and Big Horn county line on National Forest land adjacent to the Crow Indian Reservation, according to fire officials.
A pre-evacuation warning has been issued for the Sage Creek area.
Three large airtankers were conducting retardant drops Wednesday, and a helicopter and one BLM wildland engine were also deployed to battle the blaze.
(First Report) A wildfire was discovered Tuesday evening in the Pryor Mountains.
The Billings Interagency Dispatch Center estimates the Crooked Creek Fire is burning 500 acres and is located just southwest of the Crow Reservation in Carbon County.
Details on terrain and fire fighting efforts have not been released.