The child, known to authorities only as Baby Jane Doe, was lifeless when she was found in New Castle Township on June 13, 1993, troopers said in a release.
She was wrapped in a blanket and a bath mat before being placed in the bag, state police said. In a 1993 article, the Allentown Morning Call reported that the bag was thrown into the woods from the north edge of Darkwater Lane, about three-quarters of a mile off State Route 61.
At that time, police called her death "suspicious" but pathologists were unable to find signs of trauma during the autopsy, the newspaper said. Bone and tissue samples were taken for DNA testing, but a match was never found.
State police now hope that someone will recognize the bath mat she was wrapped in. A $5,000 reward is being offered for information that leads to a break in the case.
Anyone with information is asked to call the Pennsylvania Crime Stoppers at 1-800-472-8477 or submit an anonymous tip online.
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