India, June 2 -- The disappearance of 84-year-old Nancy Guthrie continues to puzzle investigators more than four months after she vanished from her home in Tucson, Arizona. Despite an extensive search operation involving federal and local authorities, widespread media coverage, and a reward exceeding $1.2 million, officials have yet to uncover any major breakthrough in the case.

As the investigation remains active, a well-known forensic expert has shared a new theory about what may have happened to Nancy Guthrie.

Forensic Expert Shares New Theory on Nancy Guthrie Case

Speaking at CrimeCon Las Vegas, veteran medicolegal death investigator Barbara Butcher discussed her views on the ongoing case. Butcher, who also hosts Oxygen's The Death I...