With the search for Nancy Guthrie continuing, there is one clue from the ransom notes that could lead to her location.

What Investigators Are Looking For

Retired FBI agent Jason Pack told Page Six that ransom notes have a "fingerprint" to them, and that some key things to pay attention to in them are word choice, tone, and how the demand is structured in order to identify that person.

"If the first two read like the same person wrote them and everything that followed reads differently, that tells the task force something meaningful about who they're actually dealing with versus who decided to insert themselves into the story once it went international," Pack said.

He added that investigators would be able to determine if the ransom notes are real based on whatever meaningful information is in them.

A Key Detail in the Earliest Notes

Pack pointed to a specific piece of evidence within the earliest communications received in the case. "The first note apparently contained specific operational details that weren't public at the time," Pack said. "Based on what's been reported, the language and tone of those first two notes compared to everything that came after is where the real analytical........

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