SIOUX FALLS, S.D. (AP) — Sioux Falls police are making another attempt to solve the death of a baby 35 years ago.

The infant known as Baby Andrew John Doe was found frozen at the bottom of an icy ditch in February 1981. The coroner at the time said the baby died of cold and blood loss, likely within two hours of his birth.

The Argus Leader reports that police exhumed the baby's skeletal remains last year and sent them to a forensics laboratory in Fort Worth, Texas, after learning about a method for extracting DNA from bones. Investigators think the technology gives them a chance to identify to whom the baby belonged.

Police Chief Matt Burns says finding out who the parents are "is a fundamental piece in getting this case solved."

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