BOISE -- Idaho officials have killed two bull bison that roamed out of Yellowstone National Park, citing concerns over the spread of brucellosis to cattle.
A spokesman for the Fremont County Sheriff's Office says one bison was killed Saturday and another Thursday in Island Park in southeastern Idaho. The area is about 15 to 20 miles west of the park.
In a statement the Idaho Department of Agriculture said the state's policy requires wild bison to be either killed or moved.
Authorities say the bison killed Thursday was along the shoulder of U.S. Highway 20 near The Nature Conservancy's Flat Ranch. The bison killed Saturday was north of Mack's Inn.
Brucellosis can cause pregnant animals to miscarry their young.