Emergency crews from several agencies responded to a fire southeast of Great Falls on Thursday afternoon.
The fire happened at the Big Stone Colony along Goon Hill Road, several miles west of Sand Coulee.
The fire started in a wood and metal-working shop.
Great Falls Fire Rescue says people were working in the building at the time, but there have been no injuries reported at this point.
As of 2:15 p.m., the fire appears to be controlled.
The cause of the fire has not yet been determined. Responding agencies included Sand Coulee Volunteer Fire Department, Black Eagle Volunteer Fire Department, Malmstrom Air Force Base, and Great Falls Fire Rescue.