Investigators have found signs of forced entry at the Arizona home of the missing 84-year-old mother of the host of NBC’s Today, Savannah Guthrie.

The host described her mother, who is believed to have been taken against her will, as “a woman of deep conviction, a good and faithful servant” in a social media post late on Monday, local time.

She asked supporters to “raise your prayers with us and believe with us that she will be lifted by them in this very moment”.

“Bring her home,” she added.

Nancy Guthrie must be found soon because she could die without her medication, Pima County Sheriff Chris Nanos said, urging whoever has her to free her.

“If she’s alive right now, her meds are vital. I can’t stress that enough. It’s been better than 24 hours, and the family tells us if she doesn’t have those meds, it can become fatal,” Sheriff Nanos said.

A photo from instagram of savannah guthrie and her mum at a sports game

Savannah Guthrie has not been on the Today show since the disappearance of her mother, Nancy. (Supplied: Instagram)

Investigators also found specific evidence in the home showing there was a night-time kidnapping, a person with knowledge of the investigation told The Associated Press.

Several of Ms Guthrie’s personal items, including her mobile phone, wallet and her car, were still there after she disappeared.

Investigators are reviewing surveillance video from nearby homes and working to analyse data from mobile phone towers.

Police are also reviewing information from numberplate cameras in the area, according to the person, who was not authorised to publicly discuss details of the case and spoke to AP on condition of anonymity.

The motive for the apparent abduction remains a mystery. Investigators do not believe at this point that it was part of a robbery, home invasion or kidnapping-for-ransom plot, the person said.

For a second day on Tuesday, Today opened with Nancy Guthrie’s disappearance, but Savannah Guthrie was not at the anchor’s desk.

Sheriff Nanos said on Monday that Guthrie was in Arizona. The host grew up in Tucson, graduated from the University of Arizona and previously worked as a reporter and anchor at Tucson television station KVOA.

Nancy Guthrie was last seen on Saturday night at her home in the Tucson area, where she lived alone and was reported missing on Sunday.

Someone at church called a family member to say Ms Guthrie was not there, leading family to search her home and then call 911, Sheriff Nanos said.

Nancy Guthrie has limited mobility, and officials do not believe she left on her own. Sheriff Nanos said she was of sound mind.

He said investigators took samples they hoped would provide at least part of a DNA profile, KVOA reported.

A missing persons alert issued by local police.

A missing persons alert issued by local police. (Supplied: Pima County Sheriff’s Department)

Searchers used drones and search dogs and were supported by volunteers and Border Patrol.

The homicide team was also involved, Sheriff Nanos said on Sunday. The FBI has offered to help, sheriff’s department spokesperson Angelica Carrillo said.

On Monday morning, Sheriff Nanos said search crews had been pulled back.

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

Even so, a sheriff’s helicopter flew over the desert on Monday afternoon near Nancy Guthrie’s home in the affluent Catalina Foothills area on the northern edge of Tucson.

Savannah Guthrie, who has two siblings, was 16 when their father died. Nancy Guthrie raised them on her own. The host often brought her mother on Today as a guest.

“She has met unthinkable challenges in her life with grit, without self-pity, with determination and always, always with unshakable faith,” the host said on the show in 2022 on Nancy Guthrie’s 80th birthday.

“She loves us, her family, fiercely, and her selflessness and sacrifice for us, her steadfastness and her unmovable confidence is the reason any of us grew up to do anything.”

AP