Savannah Guthrie’s Mom Was Possibly Kidnapped ‘in the Middle of the Night’ from Her Home: Police

Police are sharing more information about what may have happened to Savannah Guthrie’s mother, who was reported missing over the weekend.

Nancy Guthrie, 84, was last seen at her home in Catalina Foothills, north of Tucson, Ariz., around 9:30 p.m. local time, on Saturday, Jan. 31. Two days later, the Pima County Sheriff’s Department  confirmed that Nancy’s home is being investigated as a “crime scene” rather than a “search mission.”

Pima County Sheriff Nanos says in a statement shared with PEOPLE on Monday, Feb. 2, that he “believes a crime has been committed.”

“At this point, investigators believe she was taken from the home against her will, possibly in the middle of the night. Taken against her will includes possible kidnapping or abduction,” Sheriff Nanos adds.

“We have an 84-year-old woman who went to bed Saturday night and come Sunday morning, she’s gone,” Nanos tells PEOPLE in an interview on Monday. “We know, at least we believe, and I believe we know, she did not walk out of that home on her own.”

Nanos notes that Nancy’s “physical mobility was quite limited for a variety of reasons,” and that it is highly unlikely that she wandered off.

“She is really just as sharp as a tack,” Nanos tells PEOPLE. “And that too is concerning that here you have this lady who’s got all her wits about her, she knows what’s going on. So yeah, somebody came into that home, and I believe took her out there without her permission. It was against her will.”

Nanos says that police are working with different vendors to download and review home security footage, adding, “What we have done is we have taken what we believe is biological DNA type evidence, and we are submitting it to our labs, crime labs … Basically, they’ll do a rapid search.”

Nanos is thankful for those wanting to “help,” and adds, “But we really do have an obligation to protect the integrity of this investigation, of any investigation.”

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In a press conference earlier Monday, Nanos said that Nancy’s disappearance was reported on Sunday, Feb. 1, when a friend noticed she was not at church and called one of her adult children.

Savannah, 54, was absent from Today on Monday, and her co-anchor Craig Melvin said during the broadcast, “We want to get right to what is a deeply personal story for us, Nancy Guthrie, Savannah’s beloved mother, has been reported missing in Arizona.”

In a statement to the show, Savannah said, “On behalf of our family, I want to thank everyone for the thoughts, prayers, and messages of support. Right now, our focus remains on the safe return of our dear mom. We thank law enforcement for their hard work on this case and encourage anyone with information to contact the Pima County Sheriff’s Department at 520-351-4900.”