The mystery of Bethany Markowski's whereabouts has endured for 20 years.
It starts with the day she was reported missing on March 4, 2001. Her father — separated from Bethany's mother, Jonnie Carter, during a contentious divorce proceeding — told authorities he'd watched the 11-year-old go into Old Hickory Mall in Jackson, Tenn., while he stayed in a car and napped. When she hadn't returned after about two hours, he said he went looking for her, and couldn't find her.
But authorities turned up no proof that Bethany entered, exited or was seen inside the mall, Cathy Ferguson, a special agent with the Tennessee Bureau of Investigation, tells PEOPLE. Instead they believe she was last seen with her father the day before on a visit to friends of his in Little Rock, Ark., more than 200 miles away.
The father "is not a named suspect," says Ferguson. But "he's not been very cooperative, and he has not participated in the investigation at all."
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