JACKSON, Wyo. (AP) Authorities say a 55-year-old Colorado man on a guided climb died while descending the highest mountain in Grand Teton National Park.

The Associated Press reports Gary Miller, of Colorado Springs, Colo., slipped in a snowfield and slid into an icy water moat on the Lower Saddle of the Grand Teton on Thursday evening. A water moat is a gap between the top of the snowfield and the facing rock wall.

Park spokeswoman Jenny Anzelmo-Sarles says Miller's death is under investigation. Meanwhile, Teton County Coroner Kiley Campbell says Miller suffered little trauma, and drowning is not suspected.

Miller had successfully summited the Grand along with a party being led by Exum Mountain Guides, whose staff declined to comment.