What to know about the disappearance of Nancy Guthrie, mother of 'Today' show's Savannah Guthrie

Authorities are looking for the 84-year-old mother of “Today” show host Savannah Guthrie after they say she was forcibly taken from her home in Tucson, Arizona, over the weekend.

There's added urgency in the search for Nancy Guthrie, last seen Saturday night, because she could die without her medication, Pima County Sheriff Chris Nanos has said.

Investigators have shifted tactics since the weekend and now say they're investigating Nancy Guthrie’s disappearance as a crime rather than a rescue mission. That's in large part because there were signs of forced entry at her home, according to a person familiar with the investigation, who was not authorized to publicly discuss details of the case and spoke to The Associated Press on condition of anonymity.

Nanos has declined to detail the evidence investigators have, and wouldn't say whether Guthrie’s disappearance was random or targeted. Investigators have not identified a suspect or a person of interest as of Wednesday.

Here’s what to know about the case:

She disappeared from a quiet, affluent neighborhood

Nancy Guthrie lived alone in the upscale Catalina Foothills area and was last seen at her home around 9:30 p.m. Saturday. She was reported missing midday Sunday after someone at her church called a family member to say Guthrie wasn’t there, leading family to search her home and then call 911, Nanos said.

Guthrie has limited mobility, supporting the theory that she was taken against her will, but the sheriff said she is of sound mind.

Guthrie’s brick house has a gravel driveway and a yard covered in wispy trees, prickly pear and saguaro cactuses that tower over the height of her home and partially block the view of her front door from the road. Homes in her hilly neighborhood are set far apart, separated from any road traffic by large driveways and heavy front gates. The winding streets don't appear to have streetlights, casting the area into darkness after dusk and making it less likely that security cameras captured helpful footage of Guthrie's disappearance.

Jim Mason, longtime commander of a search and rescue posse for the Maricopa County Sheriff’s Office, said desert terrain can make looking for missing people difficult. Sometimes it’s hard to peer into areas that are dense with mesquite trees, cholla cactus and other brush, he said. His group is based 175 miles (280 kilometers) north of Tucson, and is not involved in the search for Guthrie.

Initially, searchers used drones and dogs alongside volunteers and Border Patrol, the sheriff said. But by Monday morning, Nanos said search crews across the dense desert habitat surrounding Guthrie's house were pulled back.

Asked Tuesday whether officials were looking for her alive, he said, “We hope we are.”

Key physical evidence but motive remains a mystery

There were signs of forced entry at Guthrie's home.

“We don’t see this as a search mission so much as it is a crime scene,” the sheriff said.

Several personal items, including Guthrie’s cellphone, wallet and car, were all still there, the person familiar with the investigation said. Investigators were reviewing surveillance video from nearby homes and information from area license plate cameras and analyzing local cellphone towers data, according to the person.

The motive remains a mystery. Investigators do not believe the abduction was part of a robbery, home invasion or kidnapping-for-ransom plot, the AP source said early Tuesday.

Unspecified DNA samples have been gathered and submitted for analysis as part of the investigation. “We’ve gotten some back, but nothing to indicate any suspects,” the sheriff said.

Public calls for help

Later Tuesday, multiple media organizations reported receiving purported ransom notes that they handed over to investigators. The sheriff’s department said it’s taking the notes and other tips seriously but declined to comment further. The Pima County sheriff and the Tucson FBI chief urged the public to offer tips during a news conference Tuesday.

At least one church as far away as Albany, New York, is offering a $25,000 reward for information that would lead to finding Nancy Guthrie.

In a social media post late Monday, Savannah Guthrie asked supporters to “raise your prayers” for her mother, and “believe with us that she will be lifted by them in this very moment. Bring her home.”

The White House says President Donald Trump called and spoke with Savannah Guthrie on Wednesday. Speaking to reporters in the Oval Office the day before, the president called the situation “terrible.”

“I always got along very good with Savannah,” Trump said.

A strong mother figure

Savannah Guthrie has been in Arizona this week and hasn’t appeared at the anchor’s desk.

She grew up in Tucson, the youngest of three siblings. She graduated from the University of Arizona and previously worked as a reporter and anchor at KVOA-TV in Tucson, joining “Today” in 2011 and becoming co-anchor the following year.

Before her disappearance, viewers got to know Nancy Guthrie through her daughter’s show. Savannah Guthrie credited her mom with holding their family together after her father's heart attack when she was 16.

“When my dad died, our family just hung onto each other for dear life because it was such a shock. We were just trying to figure out how to become a family of four when we’d always been a family of five,” she said on “Today” in 2017.

During an appearance in a story Savannah Guthrie did about her hometown late last year, she was asked what made the family want to plant roots in Tucson in the 1970s.

“It’s so wonderful. Just the air, the quality of life,” Nancy Guthrie said. “It’s laid back and gentle.”