Walmart surveillance becomes key evidence in Nancy Guthrie disappearance as investigators use retail data to narrow suspects, says expert Jason Pack.

Retired FBI agent Jason Pack recently shared what he believed could lead to the turning point in the investigation of the disappearance of Savannah Guthrie's mother, Nancy Guthrie

Retired FBI agent Jason Pack said that the bureau’s Cellular Analysis Survey Team (CAST) is among the most valuable tools in missing-person investigations.

An ex-FBI agent is questioning whether Savannah Guthrie and her family members quietly paid the ransom for their missing mother, Nancy, RadarOnline.com can reveal. Jason Pack, a retired FBI hostage negotiator, spoke out in an interview with Fox News to share his insights.

FBI video forensics experts brought specialized equipment to missing Arizona woman Nancy Guthrie's home as an intensive search operation enters its 12th day.

Retired FBI supervisory special agent Jason Pack analyzes the emotional video plea from Nancy Guthrie's family, including Savannah Guthrie, and the latest on the investigation to find her.

Both the Pima County Sheriff's Department and the FBI are investigating the disappearance of Nancy Guthrie, with rumors circulating that the two agencies are not working well together. Jason Pack, a former FBI supervisory agent,

As the search continues for Savannah Guthrie’s missing mother, Nancy Guthrie, all eyes are on the case — and many people are wondering why a white tent was placed outside the 84-year-old’s home.

The investigation into Nancy Guthrie's disappearance has highlighted the role of doorbell cameras, as images and videos captured by her device at her home in Tucson, Arizona, have become central to the case.