The Pima County Sheriff's Department, backed by FBI resources, has taken an individual into custody for questioning concerning Nancy Guthrie's kidnapping, according to a law enforcement official familiar with the case.

The person was captured at a site south of Tucson, the source disclosed, whilst law enforcement readies plans to examine premises associated with the detained individual.

The breakthrough emerged after authorities initially published images depicting a masked figure nearing Nancy Guthrie's front door whilst investigators continued neighbourhood sweeps.

Nevertheless, no evidence released so far suggests the detained individual matches the person appearing in the recently released video recordings.

Earlier Tuesday, FBI Director Kash Patel unveiled images and video of an "armed individual" connected to Nancy Guthrie's vanishing, the 84-year-old mother of "Today" show presenter Savannah Guthrie.

Armed intruder footage

The images depicted someone wearing a mask, gloves and rucksack, armed with a holstered handgun at the front entrance of Nancy Guthrie's Tucson-area residence around the time investigators suspect she was taken on 1 February.

Patel stated in his post: "[L]aw enforcement has uncovered these previously inaccessible new images showing an armed individual appearing to have tampered with the camera at Nancy Guthrie's front door the morning of her disappearance."

The Guthrie family viewed the images prior to public disclosure, law enforcement sources informed ABC News.

Savannah Guthrie shared the images on her Instagram account with the message: "We believe she is still alive. Bring her home."

In a second Tuesday afternoon Instagram post, Guthrie wrote: "Someone out there recognizes this person. We believe she is still out there. Bring her home."

Nancy Guthrie was removed from her home on Sunday, 1 February, according to authorities.

A Monday ransom deadline established by individuals claiming to be Guthrie's captors elapsed as the search persists.

Technical recovery operation

Patel revealed the FBI and Pima County Sheriff's office collaborated with "private sector partners" in recent days to retrieve the video footage, which Patel indicated had been "lost, corrupted, or inaccessible due to a variety of factors, including the removal of recording devices."

Patel explained: "The video was recovered from residual data located in the backend systems. Working with four partners -- as of this morning, law enforcement has uncovered these previously inaccessible new images showing an armed individual appearing to have tampered with the camera at Nancy Guthrie's front door the morning of her disappearance."

White House press secretary Karoline Leavitt disclosed President Donald Trump received briefings on the latest case details and was examining the video footage Patel posted online.

Leavitt stated: "We're just praying for the safety of Nancy Guthrie and that she will return home soon. And the president directed me to please encourage all Americans with any information to call the FBI, and we hope that this case will come to a positive resolution as soon as possible."

The latest case development emerged one day following Savannah Guthrie's impassioned public appeal to help resolve her mother's disappearance.