TUCSON, Ariz. — According to an expert, it is highly unlikely that Nancy Guthrie was taken across the southern border into Mexico, largely due to the stringent security measures enforced by federal officials there.

Retired NYPD Lt. Darrin Porcher highlighted the formidable border wall near Nogales, Arizona, located about 60 miles from Tucson, where Guthrie resides. He described the wall as towering and fortified with barbed wire, extending for miles beyond the city in both directions.

“Considering the current design of the border wall, crossing from the United States into Mexico presents considerable challenges since this is not an easily penetrable area,” Porcher explained to Fox News Digital while at the Nogales border crossing, which divides Nogales, Arizona, from Nogales, Sonora, Mexico.

The investigation into Nancy Guthrie’s disappearance has now entered its third week.

Porcher also pointed out the numerous surveillance cameras lining the border, along with U.S. Border Patrol agents positioned in vehicles a few hundred yards apart in certain stretches.

Although authorities have found no evidence suggesting that Guthrie, aged 84, was taken across the southern border, the protocols related to her alleged kidnapping automatically activate federal responses.

Despite the logistical problems of taking a captive across the border, Porcher said law enforcement should have immediately begun looking into the possibility, given Mexico’s proximity to Guthrie’s home. 

“I believe this is something that law enforcement should have attached too immediately within the first 72 hours, because it seems as if they were coming into a brick wall and not gaining any solutions as it relates to a kidnapping occurring,” he said. 

Experts have said that it remains unlikely that Nancy Guthrie  was taken to Mexico in a cross-border abduction.  (Fox News Digital; Getty Images)

“This is a point of contention that should have been addressed early on in the investigation,” he added. 

Mexican authorities in Sonora have disputed claims that the FBI has asked them for help in the search for Guthrie , who was last seen at her home in the Catalina Foothills, Ariz., the unincorporated community where Nancy Guthrie’s home is located.

The office of Sonora Attorney General Gustavo Rómulo Salas Chávez wrote on the social platform X in Spanish that “it has not received a formal request for collaboration in the case of a missing person in Arizona,” referring to Guthrie.

“To date, this institution has not received any formal request for collaboration, assistance, or exchange of information from U.S. authorities or Mexican federal agencies in relation to said case,” Chávez’s office added. 

Pima County Chris Nanos has said that investigators have had any indication that Guthrie  was taken across the border. 

“We know where Mexico is in relationship to this, and it’s a possibility. But no, we have nothing to indicate that,” he previously said.