A rental car belonging to 25-year-old Peter Louis Kastner, of Oklahoma City, Oklahoma, was discovered at the Hellroaring Trailhead in the north central section of Yellowstone National Park early Monday morning. He had not applied for a permit to camp overnight in the backcountry at one of the many campsites along the trail system in the area which leads to and parallels the Yellowstone River.

A subsequent investigation revealed the red Cadillac STS sedan with Oklahoma plates had been rented a month earlier and was two weeks overdue. Family members who were then contacted reported they had not been in touch with Kastner in recent weeks, and reported him missing.

Kastner is described as 6 foot 1 inch tall; 185 pounds, with brown hair and hazel eyes. Based upon information from his family he was honorably discharged from the Marine Corps after serving for four years. During his service, he was injured twice by Improvised Explosive Devices while serving in Iraq. He had moved to Oklahoma City from the Minneapolis-St. Paul, Minnesota, area to attend college.

His family is concerned about his mental state, and said he was suffering from Post Traumatic Stress Syndrome related to his injuries.

A series of searches by ground teams and dog teams have failed to turn up any clues to his whereabouts, as has a call for the public to report any sightings of Kastner in the area prior to Monday morning.

Investigators still believe he is in the park. Search efforts are slated to ramp up again this weekend, as ground searchers and dog teams will again focus on the backcountry northwest of Tower Junction. Cloudy, rainy weather, a low ceiling, and a lack of a focused search area has led searchers to focus efforts on the ground rather than utilizing helicopters or fixed wing aircraft.

There is a chance Kastner is no longer in Yellowstone. Investigators in the area are asking anyone who may have seen or been in contact with Kastner in recent weeks to call Yellowstone National Park at 307-344-7381.

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