Cause Of Death Determined For Man Found In Yellowstone NP; Brother Still Missing

An autopsy has been completed on 67-year-old Mark O’Neill whose body was found on the east shore of Shoshone Lake in Yellowstone National Park Monday, Sept. 20.

The autopsy determined the cause of death of O’Neill was exposure (hypothermia).

O’Neill, from Chimacum, Washington, along with his brother, 74-year-old Kim Crumbo, from Ogden, Utah, were reported overdue by a family member Sunday, Sept. 19 from their four-night backcountry trip to Shoshone Lake.

Search and recovery efforts continue at the lake to locate Crumbo.

Crews from the National Park Service’s Submerged Resources Center are using sonar equipment to detect clues in the water.

Park crews continue to search for Crumbo by foot and boat, with assistance from Grand Teton National Park’s interagency helicopter and dog teams from Western Montana Search Dogs.

These recovery efforts will continue for the next several days as conditions warrant.