The Pima County Sheriff's Office in Arizona confirmed Tuesday that it is aware of reports of ransom notes related to the disappearance of "TODAY" show co-anchor Savannah Guthrie's mother, and said it is investigating all leads.

The update occurred shortly after TMZ reported that it received an unverified ransom note related to Nancy Guthrie's disappearance and possible kidnapping, which demanded a "substantial amount" of Bitcoin cryptocurrency for her return.

Nancy Guthrie, 84, was last seen Saturday night in her home outside Tucson, according to a missing persons flyer, NBC News reported. Her family reported her missing around noon Sunday, Pima County Sheriff Chris Nanos said Monday.

"We are aware of reports circulating about possible ransom note(s) regarding the investigation into Nancy Guthrie," officials wrote in a statement. "We are taking all tips and leads very seriously. Anything that comes in, goes directly to our detectives who are coordinating with the FBI."

Nanos said during a press briefing Monday that aspects of the scene at the home caused "grave concern," and that authorities believe Nancy Guthrie was taken from her home instead of wandering out because she could not walk more than 50 yards on her own due to mobility issues. 

The sheriff said Tuesday that investigators have completed their investigation of Nancy Guthrie's house and did not find any footprints or tire tracks around the house or property. 

He also noted that investigators have sent in "all kinds of" DNA samples and have "gotten some back, but nothing to indicate any suspects."

Misty Severi is a news reporter for Just The News. You can follow her on X for more coverage.