Officials have closed part of the Custer Gallatin National Forest in southwestern Montana after a hunter was severely mauled by a grizzly bear. The hunter was tracking a deer on Friday when the bear attacked. Others in the hunting party called 911, and the hunter was taken by air ambulance to a nearby hospital. The attack happened south of Big Sky, a popular resort area about 55 miles (88.5 kilometers) north of Yellowstone National Park. The U.S. Forest Service implemented an emergency closure in the area near the attack while authorities seek the bear, which they said may have been shot.