Nancy Guthrie Update: Sheriffs Remain 'Stuck' on Key Aspect

Nancy Guthrie has now been missing for more than two weeks, and while authorities continue to work various leads in the search for the 84-year-old mother of three, they remain unsure about a motive for the kidnapping.

Pima County Sheriff Chris Nanos admitted as much in a new interview with the Daily Mail, published Monday morning.

Motive still a mystery

Contrary to a local report, Nanos said Guthrie's disappearance is a kidnapping, not a burglary gone bad.

It's finding the reasoning behind the abduction that has proven elusive gor law enforcement.

"This is somebody who's disappeared from the face of the earth, and now we have a camera that says here's the person who did this," Nanos told the Daily Mail.

"And that's what makes me say this is a kidnapping. The motivation for it is where we get stuck, right? Is it for money? I mean, we had the one demand where they asked for money. But is it really for money, or is it for revenge for something?"

In total, Nanos says law enforcement has received up to 50,000 tips regarding Guthrie's case.

FBI issues update on possible glove breakthrough

Over the weekend, the FBI revealed that a glove located in a field roughly two miles from Nancy Guthrie's home may match ones worn by the possible suspect captured in the surveillance video images released last week.

“The one with the DNA profile recovered is different and appears to match the gloves of the subject in the surveillance video,” an FBI spokesperson told Fox News.

Savannah Guthrie speaks out

In a new video released on Instagram Sunday night, Savannah Guthrie, Nancy's daughter and the co-host of Today, said she and her siblings "still have hope and still believe" their mother is alive.

Savannah went on to send a brief, but pointed, message to whoever is responsible for her mother's kidnapping.

“It’s never too late and you’re not lost or alone,” she said. “It is never too late to do the right thing. We are here. We believe, and we believe in the essential goodness of every human being. And it’s never too late.”