DULUTH (AP) - The Minnesota Department of Natural Resources says a wildfire in Aitkin County has burned at least 2,500 acres, but isn't threatening any people or structures.

     DNR incident commander Brian Pisarek expects the fire to be contained Friday afternoon. 
The fire is burning near Tamarack and started Thursday afternoon. High winds and dry conditions helped the fire spread at a speed of 2 to 3 mph in the late afternoon and evening. 
     Five air tankers and a helicopter were used to drop flame retardant and water. Overall, a total of 88 fires burned about 3,500 acres in Minnesota Thursday.