The "July Fire" burning near Zortman and Landusky is now suspected to have been caused by a person or people.
There is no word yet whether it was intentional or accidental, but a source told MTN News last week that he saw what appeared to be remnants of a campfire in the area where the fire originated.
Law enforcement officers for the federal Bureau of Land Management confirmed that they suspect it is human-caused, but are not releasing any further information at this time as the investigation continues.
There have been no reported injuries.
On Tuesday, officials determined that one burned structure, originally thought to be an outbuilding, was actually a small recreational cabin.
The fire was reported on Monday July 3rd.
As of Tuesday afternoon, the fire has burned an estimated 11,093 acres, and is 60% contained.
Fire officials estimated that they could have 100% containment by Friday, July 14th.
The fire is contained on the east flank and has not crossed State Route 66 to the south or Seven Mile Road to the east.
The fire is within 1/2 mile of the Fort Belknap Reservation and Blaine County.
There are about 440 personnel assigned to the fire.
The cost so far of fighting the fire is about $3.2 million.
PREVIOUSLY: July Fire explodes to 8,300+ acres