The 59-year-old hiker founded dead on a trail in Yellowstone National Park on Friday was killed by a bear, according to the National Park Service.

Results from an autopsy conducted Sunday afternoon concluded that John Wallace, from Chassell, Mich., died as a result of traumatic injuries from a bear attack, according to a press released issued by Yellowstone officials.

Wallace's body was discovered Friday morning by two hikers along the Mary Mountain Trail, about five miles west of the Hayden Valley trailhead, which is off the Grand Loop Road between Mud Volcano and Canyon Junction. The twenty-one-mile-long trail crosses the center of Yellowstone, connecting the west and east sides of the lower portion of the Grand Loop Road.

Rangers discovered signs of grizzly bear activity at the scene Friday afternoon, including bear tracks and scat.

Wallace was traveling alone, and had pitched a tent in a park campground sometime Wednesday.

The Mary Mountain Trail, the Cygnet Lakes Trail, and the section of the Hayden Valley west of the Grand Loop Road have been closed to hikers.

Park rangers, wildlife biologists, and park managers continue their investigation of the incident.

Visitors are advised to stay on designated trails, hike in groups of three or more people, be alert for bears, make noise, carry bear spray, and not to run upon encountering a bear.

Hikers and backcountry users are encouraged to check with staff at Park visitor centers or backcountry offices for updated information before planning any trips in the central portion of the Park.

This is the second bear-related death in Yellowstone National Park this summer. Pharmacist Brian Matayoshi, killed by a grizzly sow earlier this summer, was on his fourth visit to Yellowstone National Park with his wife, Marylyn; they had never seen a bear on previous visits.

RELATED STORIES: Yellowstone Grizzly Victim Identity Released; No Search for Yellowstone Killer Grizzly: NPS; Grizzly Kills Yellowstone National Park Hiker

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