Pima County Sheriff Chris Nanos has reacted after it was claimed a new letter sent from someone claiming to have a video of missing Nancy, the mother of US TV host Savannah Guthrie.

The TMZ reported on Friday that it had received a new letter from someone, where the person alleged there are two people responsible for Nancy’s kidnapping and a video on a phone in a secure location shows the “main guy” and Guthrie that was captured on “the day that was probably her last.”

Commenting on the reports, Chris who has been leading the investigation into Nancy kidnapping, responded saying, “I think the FBI has done a number of arrests for false or fake ransom notes.

“It's a shame that that happens, but I think we're looking at another one of those today.”

Sheriff released the statement during an interview after Savannah said Tuesday she is in "agony" after reports Nancy died shortly after being abducted.

Savannah also pleaded for anyone with information about the disappearance of Nancy Guthrie, 84, to contact authorities.

"I wanted to just take the opportunity to ask people, to really... to beg people to come forward, somebody knows something," she told viewers of NBC´s Today show.

"This is a news story today that is on your radar, but this is the life that my sister lives, that I live, that my brother lives, that our extended families live, that our children live every day, and we are in agony, we cannot be at peace.

"This is a moment to tell you that we need your help."