A retired Arizona law enforcement official believes missing Nancy Guthrie may have been taken to Mexico, citing Tucson's proximity to the border and his experience investigating crimes in the region.
Dave Smith, a former lieutenant with the Arizona Department of Public Safety, told Fox News Digital that the 84-year-old mother of Savannah Guthrie may have been transported across the border after disappearing from her Tucson home on February 1.
'My first thought is always Mexico in a major crime, because it's a great haven, and it's hard for us to follow up on,' Smith told Fox News Digital.
Smith noted that Tucson is located about 60 miles from the border, making that scenario a 'strong possibility.'
Smith also noted that the masked suspect seen on surveillance footage recovered from Guthrie's Nest doorbell camera appeared to be carrying a holstered pistol in what he described as 'Mexican carry' style.
Guthrie vanished in what investigators believe was a kidnapping.
Smith said the rugged terrain surrounding Tucson has complicated the search.
'The whole Tucson Valley is literally built around these arroyos, these ephemeral rivers,' he said. 'It's like a giant alley through the neighborhoods.'
Retired Arizona law enforcement official Dave Smith said he believes that Nancy Guthrie may have been taken to Mexico
The 84-year-old mother of NBC News Today anchor Savannah Guthrie disappeared on February 1 and police believe she was kidnapped from her home
He said the desert offers countless hiding places while also quickly destroying evidence.
'The evidence is transitory,' Smith said. 'Once it rains, your footprints go away, the sun is hard on other forms of evidence and frankly this is a tough place to investigate crimes.'
Despite that, Smith said he believes Guthrie was likely taken far beyond the Tucson area.
'The desert itself is a great place to dump a body,' he said. 'But in this case, obviously there was somebody who was taken with intent. And I think that's why we need to wonder, perhaps, was she taken to Mexico?'
Smith said years of investigating crimes near the border informed his theory.
'So many times when we were investigating crimes down here, Mexico was the answer,' he said.
'We recovered hundreds and hundreds of stolen vehicles across the border. If you kidnap someone, why wouldn't you take them over there?'
He said it would be easier for a suspect to hide in Nogales, Sonora, which has a population of roughly 300,000.
Smith said the harsh terrain surrounding Tucson has made the investigation especially difficult
Surveillance footage also captured a masked person outside Nancy Guthrie's front door, appearing to tamper with the doorbell camera before it was snatched off
Smith also noted that the masked suspect seen on surveillance footage appeared to have tucked his gun into his waistband.
He suggested tensions between local investigators and the FBI may be tied to concerns that evidence pointing to Mexico would have made the case a federal investigation.
Sheriff Chris Nanos and FBI Director Kash Patel have publicly disagreed over how quickly federal authorities were brought into the case.
'My personal theory is, if Mexico was suspected, that would make it a federal investigation,' Smith said.
'There seemed to be a great deal of effort to keep the feds out of this case.'
Smith stressed that many people underestimate how difficult southern Arizona is to search.
'Most people, when they think of desert they think of the Sahara and the sand dunes,' he said. 'This is so much more difficult.'
No suspects have been publicly identified since Guthrie's disappearance.
Smith said Tucson’s geography makes investigating Guthrie's disappearance extremely difficult
Police believe Nancy Guthrie was kidnapped from her Tucson, Arizona home (pictured)
Human bones were found close to her Tucson, Arizona home on Thursday but they were quickly determined to be unrelated to her
This comes after human bones were found near the Tucson home of the missing 84-year-old, though officials later ruled out the remains as belonging to Guthrie.
Police and FBI agents searched a desert area about 15 minutes from Guthrie's home on Thursday after bones were discovered, but Tucson Police later confirmed they were 'prehistoric' and unrelated to the missing grandmother's case.
The high-profile investigation has involved FBI and Pima County detectives probing ransom messages demanding bitcoin payments, though no proof of life was ever provided and no arrests have been made.
Investigators have uncovered several pieces of evidence at the home, including blood drops on the porch, a ripped-off doorbell camera, gloves, and surveillance footage showing a masked person tampering with the camera before it disappeared.
Savannah Guthrie recently returned to NBC's Today after stepping away during the search for her mother.
The FBI is still offering a $50,000 reward for information about Nancy's whereabouts.