Sheriffs investigators say they are working with biological evidence at the home Nancy Guthrie disappeared from about two and a half weeks ago.
The latest update from the Sheriffs department is not more specific about that evidence.
Interest in the case is so high that the Sheriffs Department and FBI have been flooded with thousands and thousands of tips. They propel the investigation. But how do detectives decide which tips to check first?
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The Sheriffs Department says it has taken in 18,000 tips and counting. Naturally, it has to identify and act on the hottest tips first.
Sheriff Chris Nanos says when investigators return to a site over and over, its not that they missed something; they come back because a credible new tip suggested looking for something new.
Even with hundreds of deputies working the case, thousands of tips mean theyve turned to software to sort tips and set priorities for checking them out.
Priorities rank one to four.
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The Sheriff says, Heres a level one tip-that video-the doorbell. That would be a great example of a level one tip or maybe its, hey, this backpack has been identified as only purchased at Walmart. Thatll be pretty high.
Nanos wants those tips to continue to pour in and let deputies decide if they fill in a piece of the puzzle.
He says he is still optimistic and says hell worry when the tips slow down.
Because let’s face it, youve been around enough to know that when these tips dry up this case goes cold. We believe somebody out there knows who did this. We need that person to call,” he said.
This story was originally published by Craig Smith with the
Scripps News Group station in Tucson.