A score of Federal Bureau of Investigation agents returned to the site where Nancy Guthrie went missing: her home in Tucson, according to reports, illuminating the alleged pressure on the agency to take a larger role in the case as questions rose over the leading investigator Pima County Sheriff's Department's handling as six months passed since the 84-year-old's disappearance.

According to Fox News Digital, which interviewed the missing person's neighbour, who told the outlet the authorities combed the area behind Savannah Guthrie's mom's property, which is mostly desert.

Sheriff Chris Nanos, meanwhile, the head of the investigation, recently shared that officers are reviewing “literally tens of thousands” of videos.

Doubling down on the effort the detectives are pouring into, he said, “What happens daily is the team looks at these videos, and really they’re just kind of compartmentalising them.”

The timing of the FBI's return to Nancy's home comes after a report in Axios stated the pressure the agency is under to take a leading role, whereas they are currently assisting one.

The disappeared 84-year-old's family, especially her daughter Savannah, is refusing to give up hope, despite one of the alleged ransom notes claiming she passed away.

"We will never stop looking for answers – and we will never stop looking for the light. We will always be hoping and praying and believing in the best of our world – in spite of circumstance. This is what our faith makes possible," the TODAY anchor's recent emotional plea on Instagram read.