News9.com

YELLOWSTONE NATIONAL PARK, Wyoming -- The body of an Oklahoma man, who has been missing since May, has been discovered in Yellowstone National Park.

Authorities said a group of researchers were hiking in the park July 14 when they came across the remains of 25-year-old Peter Louis Kastner.

An autopsy revealed Kastner died of a self-inflicted gunshot wound.

Kastner was reported missing May 31 after his rental car from an Oklahoma City car rental agency was discovered inside the park and was two weeks overdue.

Kastner served four years in the Marine Corps before being honorably discharged. During his service in Iraq, Kastner was injured twice by IEDs.

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