5 MINUTES AGO: Police point to the moment Nancy, Savannah Guthrie’s mother, was abducted, right as she stepped out the door, from front porch surveillance footage suggesting the worst-case scenario is….

Savannah Guthrie and mother Nancy Guthrie.Credit : Nathan Congleton/NBC via Getty

What began as an urgent search mission has become a “crime scene” after Nancy Guthrie, the 84-year-old mother of Today co-anchor Savannah Guthrie, was reported missing over the weekend, an Arizona sheriff has said.

Savannah Guthrie was absent from the Today show on Monday, Feb. 2, amid the investigation, with colleagues acknowledging the personal nature of the situation during the broadcast.

“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,” Savannah wrote in a statement shared with Today.

The Pima County Sheriff’s Department has confirmed that Savannah is in Arizona and that her family is cooperating with investigators.

Here’s everything to know about Nancy Guthrie’s disappearance so far.

She Didn’t Show Up at Church, Sparking Concern

Pima County Sheriff Chris Nanos said during a press conference that Nancy’s disappearance was first reported on the morning of Sunday, Feb. 1, after a friend from her church noticed she was not at services and called one of her adult children.

Nancy had last been seen around 9:30 p.m. on Saturday, Jan. 31 at her residence near East Skyline Drive and North Campbell Avenue.

Family Checked the House, Then Called 911

They then went to Nancy’s home in Catalina Foothills, north of Tucson, Ariz., to check on her, and “did some searching and realized, ‘We need some help,’ and they called 911,” the sheriff said.

What investigators encountered next, the sheriff said, quickly raised concerns.

‘Concerning’ Scene at Nancy’s Home Prompts Homicide Investigation

On Sunday, the sheriff said a search-and-rescue mission involving airplanes, drones, helicopters, and specially trained dogs had begun after authorities found a “concerning” scene at Nancy’s home. Homicide detectives were also involved in the investigation, he said.

“We get these calls quite often, and we do a good job of searching the area,” Nanos said. “But, this one stood out because of what was described to us at the scene and what we found and located just in looking at the scene.”

“I hope we find her safe and sound, but we can’t ignore what’s in front of us,” Nanos added.

Sheriff Clarifies Nancy Has ‘No Cognitive Issues’

While speaking to reporters, Nanos said Nancy is “not in good physical health” and may have been exposed to cold weather all night.

But he added, “She has no cognitive issues at all.”

“She’s very alert, of good, sound mind,” he said. “Just some physical ailments that limit her ability to move around,” Nanos said.

Sheriff Confirms ‘Crime Scene’

The sheriff shared an update on the investigation on Monday, Feb. 2, saying at a press conference that Nancy’s home is being treated as a “crime scene” rather than a “search mission.”

“This is an 84-year-old lady who suffers from some physical ailments, has some physical challenges, is in need of medication — medication that, if she doesn’t have in 24 hours, it could be fatal,” Nanos said.

Want to keep up with the latest crime coverage? Sign up for PEOPLE’s free True Crime newsletter for breaking crime news, ongoing trial coverage and details of intriguing unsolved cases.

He also made a “plea” to “anyone who knows anything about it, who has seen something, heard something, to contact us. Call 911. We don’t need another bad, tragic ending. We need some help.”

The PCSD describes Nancy as a female with brown hair and blue eyes. She is 5 feet 5 inches tall and weighs around 150 lbs.

Anyone with information is asked to contact the Pima County Sheriff’s Department at 520-351-4900.