An act of revenge has not been ruled out as a possible motive for Nancy Guthrie’s disappearance, according to Pima County Sheriff Chris Nanos.

In an interview with the Daily Mail published on Monday, Feb. 16, Nanos revealed that detectives are still determining the intentions of the suspects involved in Nancy’s vanishing. The 84-year-old mother of Today show co-host Savannah Guthrie was reported missing on Feb. 1, having been last seen at her Tuscon, Arizona, home the day before.

Nanos explained to the Mail why he believes Nancy was kidnapped, rather than the victim of a burglary gone wrong.

“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,” he told the outlet, referring to the masked intruder captured on a camera at her home.

Savannah and Nancy Guthrie.savannahguthrie/Instagram

Nanos continued, “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?”

The sheriff, who has 50 years of experience in law enforcement, revealed that up to 50,000 tips have been received regarding Nancy’s disappearance, per the outlet.

Pima County Sheriff’s Department

He also previously shared that it could take “years” to find Nancy.

“Maybe it’s an hour from now,” Nanos said of how long it could take to locate Nancy, per The New York Times. “Maybe it’s weeks or months or years from now. But we won’t quit. We’re going to find Nancy. We’re going to find this guy.”

“The one with the DNA profile recovered is different and appears to match the gloves of the subject in the surveillance video,” said the FBI spokesperson in a statement obtained on Sunday, Feb. 15.

FBI and SWAT units searching for Nancy Guthrie on Feb. 13.Brandon Bell/Getty

Savannah, 54, made an emotional plea to her mother’s kidnappers in an Instagram video shared later that day.

“I wanted to say to whoever has her or knows where she is that it’s never too late. And you’re not lost or alone,” she said. “And it is never too late to do the right thing. And we are here. And we believe. And we believe in the essential goodness of every human being.”

“It’s never too late,” Savannah concluded.

A $100,000 reward has been offered for any information leading to Nancy’s recovery or an arrest in the case.

The FBI is urging anyone with tips or leads to call 1-800-CALL-FBI in addition to the Pima County Sheriff’s Office number, 520-351-4900.