“Today” show host Savannah Guthrie’s mother, Nancy, is missing in Arizona in what police believe was an abduction from her home while she slept, Pima County Sheriff Chris Nanos told CBS News on Monday.

“I believe she was abducted, yes,” Nanos said. “She didn’t walk from there. She didn’t go willingly.”

Nanos earlier Monday confirmed that her disappearance is being treated as a crime, and urged neighbors to review home video camera footage.

“We saw some things at the home that were concerning to us,” Nanos told reporters. “We believe now after we’ve processed that crime scene that we do in fact have a crime scene, that we do in fact have a crime, and we’re asking the community’s help.”

Nanos urged people who think they see Nancy Guthrie to take a picture or record a video and alert authorities. A missing person’s flier from the sheriff’s department said she is 5 feet, 5 inches tall, has brown hair and blue eyes and weighs 150 pounds.

Nancy Guthrie, 84, “is very limited in her mobility” and “we know she didn’t just walk out of there,” Nanos said, adding there are other aspects at the scene that indicate she did not leave on her own.

She doesn’t have any cognitive issues, but is in urgent need of her daily medication, authorities said.

“The clock is literally ticking,” Nanos said, referring to Nancy Guthrie’s need to take her medication. “It’s been more than 24 hours since she disappeared.”

Nanos said she lived by herself, and that the family told him “she couldn’t walk 50 yards. And so we know she couldn’t get far from that home unless she was removed from that home.”

“I want to stress to you, and it is really important: Miss Guthrie, Nancy Guthrie is of great sound mind,” Nanos told reporters. “This is not a dementia-related, she is as sharp as a tack. The family wants everybody to know this isn’t somebody who just wandered off.”

The sheriff said Nancy Guthrie was last seen at her home in the Catalina Foothills area at 9:30 p.m. Saturday. When she didn’t show up for church the next morning, family members went to her home, looked for her and called 911, he said.

Nanos didn’t provide additional details about what investigators found concerning at the home, citing the ongoing investigation. Sgt. David Stivers told reporters, “There were circumstances on scene that we believe are suspicious in nature, I think is the best way to put it.”

Nanos did not provide a possible motive and said there was no initial indication Nancy Guthrie was targeted because of her name, but noted, “We can’t dismiss that.

“We will certainly look at that and we’ll see, was she being stalked? Did she have some people out there harassing her or something?” he told CBS News.

The FBI is assisting in the investigation, two sources told CBS News.

The search and rescue team worked through the night, employing drones, helicopters and heat sensors, but have since been sent home, Nanos said Monday, as the search has turned to a criminal investigation. “Right now we don’t see this as a search mission so much as we do a crime scene,” he said.

Investigators were poring over footage from security cameras in the home and examining Nancy Guthrie’s cellphone, Nanos said. Authorities were also turning to license-plate readers and other surveillance cameras for leads in the case.

The sheriff encouraged Guthrie’s neighbors to go through their own home security footage, even if their cameras don’t face the Guthrie home.

“They still might see something,” Nanos said. “Maybe it’s somebody walking by. Maybe it’s some vehicle driving by at that time of day.”

Nancy Guthrie’s family has asked nearby residents to review their security footage captured over the weekend, especially between the hours of 1:00 a.m. and 4:00 a.m. on Sunday. When CBS News asked Nanos about the time frame, he said the department is starting with a narrow window and will expand outward.

“Keep looking. You never know what you’ll see,” Sheriff Nanos said. “Maybe it’s just a pair of headlights. But if you see something that just doesn’t seem right in that neighborhood, please let us know. We can come and download all your digital evidence and take a look at it ourselves.”

Nanos also told CBS News he didn’t know if Guthrie was harmed when she was removed from the home.

Nanos said he didn’t think that there was an active threat that posed a danger to the public.

The family was cooperating with the investigation, the sheriff said.

Savannah Guthrie issued a statement on her mother’s disappearance on Monday.

“On behalf of our family, I want to thank everyone for the thoughts, prayers and messages of support,” she said. “Right now, our focus remains on the safe return of our dear mom.”

Later Monday, Savannah Guthrie posted on Instagram, “thank you for lifting your prayers with ours for our beloved mom, our dearest Nancy, a woman of deep conviction, a good and faithful servant. raise your prayers with us and believe with us that she will be lifted by them in this very moment.”

Guthrie urged anyone with information to contact the Pima County Sheriff’s Department.