The dispute centers on forensic evidence recovered from Guthrie’s Tucson home. Investigators believe she was taken against her will in the early morning hours of Feb. 1. Blood drops matching her DNA were found near the front entrance.
Surveillance data showed her doorbell camera disconnecting at 1:47 a.m., motion detected shortly after and her pacemaker app losing connection around 2:28 a.m.
Her cellphone, Apple Watch, and life-sustaining medication were left behind.
A federal law enforcement source previously told Fox News Digital that the FBI requested access to specific items, including a glove and DNA evidence collected inside the home, so they could be processed at the bureau’s national crime laboratory in Quantico, Virginia.
According to the source, Nanos pushed instead to have the evidence analyzed by a private forensic lab in Florida that has worked with the department for years.
Nanos denied sidelining federal authorities. He said the Florida lab is already analyzing DNA profiles from the crime scene and that coordination with the FBI continues.
“Actually, the FBI just wanted to send the one or two they found by the crime scene, closest to it – mile, mile and a half . . . I said ‘No, why do that? Let’s just send them all to where all the DNA exists, all the profiles and the markers exist.’ They agreed, makes sense,” Nanos told KVOA.
He added that discussions were held on Thursday morning about potentially sending gloves to the FBI lab as well.
Scrutiny of the investigation has increased in recent days.
Critics have questioned why the department’s Cessna aircraft, equipped with thermal imaging, was not deployed until hours after Guthrie was reported missing.
Others have raised concerns about repeated entries and exits from the home and whether that could complicate the chain of custody in a future prosecution.
Federal agents have taken a more visible role.
The FBI recovered previously inaccessible doorbell footage from backend systems and released images of a masked individual appearing to tamper with the front camera.
The bureau is offering a $50,000 reward for information leading to Guthrie’s recovery.
On Friday night, a law enforcement presence remained in a Catalina Foothills neighborhood after 1:15 a.m. Saturday, following a SWAT operation linked to the Nancy Guthrie investigation. The Pima County Sheriff’s Department confirmed the operation is connected to the disappearance of the 84-year-old Tucson woman.
Dozens of law enforcement vehicles moved into the Shadow Hills neighborhood Friday, News 4 Tucson reported.
Neighbors were temporarily blocked from entering North Camino De Michael from East Placita De Graciela and East Placita De Michael.
A Pima County sheriff’s deputy continued blocking the roads to nonresidents past 1 a.m. Saturday.
Residents told News 4 Tucson they were stunned by the heavy law enforcement presence.
“Mindblowing, I like cannot believe it,” one woman who lives on Camino De Michael told News 4 Tucson. “We’re trying to figure out what house it could possibly be at. I mean, we walk these streets all the time, pretty familiar with the homes.”
The woman asked to remain anonymous.
She said she and her child were eventually allowed back into the neighborhood after 9 p.m. following a wait of roughly 90 minutes.
Two other neighbors said they had noticed law enforcement activity in the area in recent days.
One resident said two pairs of FBI officials were seen walking the street on foot on Thursday.
Another neighbor said the area typically sees very little law enforcement activity.
That resident said Pima County Sheriff’s Department vehicles had been seen in recent days and called Friday night’s developments “disturbing.”
“Disturbing to think it’s so close to my house,” the neighbor told News 4 Tucson.
