Authorities are investigating the disappearance of Nancy Guthrie, 84, who was last seen at her Arizona home on Sat. Jan. 31

Savannah Guthrie and mother Nancy Guthrie

Savannah Guthrie and mother Nancy Guthrie.Credit : savannahguthrie/Instagram

Pima County Sheriff’s Office audio dispatch recordings obtained by PEOPLE show that Nancy Guthrie, the missing 84-year-old mother of Savannah Guthrie, has high blood pressure and cardiac issues, and uses a pacemaker.

In the dispatch audio, officials also give a physical description of the mother of three, who was reported missing by her family over the weekend: “Nancy, a white female, 84 years of age, 5’2″, medium build, brown over blue. Missing after 2200 hours as of yesterday.”

Pima County Sheriff Chris Nanos said at a Tuesday, Feb. 3, press conference that authorities believe “Nancy was taken against her will.” There are no suspects in the kidnapping, and Nanos does not know if one or more person committed the presumed kidnapping.

Nancy was last seen around 9:30 p.m. on Saturday, Jan. 31, at her home near East Skyline Drive and North Campbell Avenue in the Catalina Foothills, Catalina Foothills, north of Tucson.

Authorities declared the home a crime scene because of what they said were “very concerning” conditions.

The sheriff told PEOPLE that investigators discovered “biological DNA” evidence at her home, which was Nancy’s.

Nancy has “no cognitive issues” and is “very alert, she’s of good, sound mind” but is “not in good physical health,” Nanos previously told reporters.

He also said Nancy requires daily medication. If she goes without it for more than 24 hours, it could prove life-threatening, he said.

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On Monday, Feb. 2, the sheriff told reporters at a press conference that authorities are reviewing surveillance footage and license plate readers. “We know she didn’t just walk out of there,” Nanos said.

Savannah, 54, did not appear on the Today show on Monday Feb. 2 or Tuesday, Feb. 3.

She is with her family in Arizona while police investigate what happened to her mother.

On Monday night, she posted a message on Instagram to ask people to “please pray.”

Anyone with information is asked to contact the Pima County Sheriff’s Department at 520-351-4900. People are encouraged to call 88-CRIME or 520-882-7463. All calls remain anonymous. They can also use the mobile app P3TIPS or visit 88crime.org.