FBI specialists are reportedly testing DNA from a 'rootless hair' samplerecovered inside Nancy Guthrie's Tucson home, according to a US reporter, as the case of the missing 84 year old enters a potentially important new phase and outside groups urge Arizona authorities to expand the search.

Guthrie, the mother of Today star Savannah Guthrie, was last seen on 31 January after being dropped at her Catalina Foothills home following dinner with her daughter Annie and son in law Tommaso Cioni.Investigators have said they believe she was taken in the early hours of 1 February in what they have repeatedly described as a targeted abduction. The FBI has said blood found at the scene belonged to Nancy and has released footage of a masked man on her porch, but no suspect has been publicly identified and no arrest has been made.

As the investigation appears to have slowed, the United Cajun Navy, a volunteer search and rescue group, has been pushing to join the hunt. Incident commander Josh Gill said his team submitted a41 page proposal to the Pima County Sheriff's Departmentshortly after Guthrie disappeared, setting out how they could search the difficult terrain around Tucson.

'We want permission from the lead agency,' Gill toldFox News Digital. 'I don't think there would be any harm. I think it would be one step closer to providing some closure not just to the family or the community, but to the nation.'

Gill said the group offered to work entirely under the sheriff's direction. If volunteers found anything potentially significant, they would leave it untouched and alert deputies so the chain of evidence could be preserved.

The proposed search areas included desert scrub, drainage ditches, abandoned buildings and other remote locations that can be difficult for law enforcement to cover alone. According to Gill, the organisation was prepared to deploycertified cadaver dogs, a scent tracking dog and heat detecting dronesto scan wide areas from the air.

He said the group has received no formal response.'We have not been contacted on the plan that we provided,' Gill told the outlet, adding that he remained 'open to developing a new plan with law enforcement'.

Gill also said the organisation had the manpower and experience to help. He said GPS tracked volunteers could carry out daily grid searches from 8am to 6pm. 'We've got some of the best and brightest, and our network is huge. Let us work with the sheriff's department to do what's best.'

The lack of movement has prompted pressure from outside the investigation. Independent journalist Cherise 'Pebbles' Wilson has launched aChange.orgpetition calling on Pima County to accept the United Cajun Navy's help.

'I lost my vulnerable grandmother a couple of years ago, and Nancy Guthrie's disappearance pulled at my heartstrings,' Wilson told Fox News Digital. 'Knowing that somebody took advantage of a loving lady, an elderly lady like that, is really disturbing.'

Source: International Business Times UK