Nancy Guthrie has been missing since February 1, and as the four-month milestone approaches, officials are considering introducing new tools into the investigation.
Fox News Digital reporter Michael Ruiz revealed that federal law enforcement is exploring the use of new technology in the case, although he did not provide further details.
The FBI, led by Pima County Sheriff Chris Nanos, has been working closely with the Guthrie family, including her daughter Savannah Guthrie, co-host of NBC Today.
Nanos has maintained that he followed protocol and contacted the FBI promptly, but there has been criticism over his management of the investigation.
Today marks a somber deadline, with no leads, suspects, or motives established in the case.
The Guthrie family is offering a $1 million reward for any information, and the FBI has added a $100,000 reward.
