Concern is growing for Savannah Guthrie and her family after her mother, Nancy Guthrie, disappeared from her Arizona home over the weekend under circumstances authorities now believe may involve a crime. Nancy, 84, was last seen at her home in the Catalina Foothills north of Tucson on Saturday, and after she missed church on Sunday, a friend called police, triggering a large search with ground crews and aerial teams.

At a Sunday press conference, Pima County Sheriff Chris Nanos said the case was urgent because of Nancy’s age and health. While officials initially said they couldn’t confirm criminal activity, Nanos emphasized they were deeply concerned by what they were finding at the home and confirmed a homicide team had been brought in to assist due to the seriousness of the situation.

By Monday, Nanos told People that investigators believe Nancy may have been taken from her home against her will, possibly during the night. He said she went to bed Saturday and was gone by Sunday morning, and authorities are confident she did not leave on her own—especially given her limited mobility, even though he described her as mentally “sharp.”

Investigators are reviewing nearby security footage and have collected “biological DNA-type evidence,” though details haven’t been released. Savannah Guthrie has been absent from Today and asked the public to contact the Pima County Sheriff’s Department with any information, while also sharing messages of faith and prayer as the search continues and the family asks for privacy.