Wyoming authorities have a mystery on their hands and it involves a man from Maryland.
Crews searched from the ground and the air, but have not found any sign of him.
According to park rangers, Isaac was on a cross-country trip when he was reported missing.
He stands 5-feet-8-inches tall and weighs 215 pounds. He has black hair, brown eyes and tattoos on his shoulder blades and right triceps.
Anyone with information about Isaac’s whereabouts, is urged to call Yellowstone’s communication center at (307) 344-7381.
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