The fire, burning in steep, rugged terrain, was 5 percent contained Sunday.

A number of campers and recreationalists were evacuating from the area about eight miles west of Estes Park soon after the blaze began near the Cub Lake Trail and Fern Lake before 2 p.m. on Tuesday.

"If you saw anything unusual or noteworthy, investigators would like to talk with you," the National Park Service stated Sunday.

Anyone with information can call the agency at 970-586-1399.

Read more of the story in the Denver Post.