Nancy Guthrie was reported missing from her home in the southwestern state of Arizona on Feb 1, and federal investigators last week increased the reward for information leading to her location or the arrest of her captors to US$100,000.

The FBI has released photos and video of a masked person approaching Guthrie’s home on the night of the kidnapping but has failed to identify a suspect in the case.

Pima County Sheriff Chris Nanos said on Monday that investigators had ruled out Nancy Guthrie’s family members as having any involvement in her disappearance.

“To be clear… the Guthrie family — to include all siblings and spouses — has been cleared as possible suspects in this case,” Nanos said in the statement posted to X, adding the family “has been nothing but cooperative and gracious and are victims in this case.”

“To suggest otherwise is not only wrong, it is cruel. The Guthrie family are victims plain and simple…”

Investigators have not publicly named any suspects in the case that has captivated the nation, but they have released several photographs and videos showing an individual wearing gloves, a mask and backpack approaching Guthrie’s doorstep in eerie black-and-white imagery.

A holstered gun is apparently visible on the person’s waist.

On Sunday, the FBI said investigators found DNA on a glove that appears to match those worn by the masked person. The discovery was made about two miles (three kilometers) from Nancy Guthrie’s home.

The Guthrie family has received ransom letters with payment demands, the FBI has said.

Savannah Guthrie issued another plea to her mother’s captors in an Instagram video on Sunday.

“It’s never too late to do the right thing,” she said.

“We are here… And we believe in the essential goodness of every human being.”