FBI Hunts Mystery TMZ Tipster as Investigators Bet on Human Intelligence to Break Nancy Guthrie Case

Federal investigators are actively searching for an anonymous source who repeatedly contacted TMZ claiming to know the identity of Nancy Guthrie's kidnappers and the whereabouts of her body, TMZ founder Harvey Levin told Fox News Digital on Tuesday. Authorities now believe the tipster, who communicated under multiple male aliases, may actually be a woman — a detail that has sharpened the focus of the probe.

The Tipster's Trail: Pseudonyms, Bitcoin, and Shifting Leads

Levin said the individual used several different male names across a series of messages to TMZ while consistently requesting payment in exchange for information, always routing those requests through a single Bitcoin address. Investigators told Levin they believe the sender is female, though he said they did not explain their reasoning. The FBI, which is handling the ransom-note aspects of the Guthrie investigation, declined to comment on the matter.

Levin told Fox News Digital that he had offered to pay the purported tipster contingently — solely to test whether the information held up — as part of a planned documentary on the case. Federal authorities subsequently asked TMZ to stand down on the documentary, a request Levin said the outlet honored. "We told them we wouldn't do anything without their approval, because we don't want to mess with the investigation," he said.

Forensics Hits a Wall; Investigators Pivot to Human Sources

California attorney and Fox News contributor Josh Ritter said that after nearly 20 weeks, digital forensics appear to have reached their limits without producing a breakthrough. Whoever sent the ransom notes has so far evaded identification through technical means. An FBI source told Levin — on two separate occasions — that the case is most likely to be resolved within six months to two years, and that the probable catalyst will be human: a co-conspirator who talks, a former partner who decides to go to authorities, or someone emboldened by a combined reward of more than $1.2 million that is currently on offer.

"Somebody goes to a bar and starts bragging about it, or an ex-lover decides, screw my ex, and I'm going to authorities to blow the whistle," Levin said, relaying the FBI's working theory. Ritter echoed that assessment. "This was not some professional operation," he told Fox News Digital, adding that loose-lipped accomplices have historically been a reliable weak point in exactly these circumstances.

Savannah Guthrie Renews Public Appeal

Nancy Guthrie's daughter, NBC "Today" co-host Savannah Guthrie, appeared on set Tuesday to appeal directly to anyone with information. "I just want to take the opportunity to ask people, really to beg people to come forward," she said, describing the toll the unresolved case continues to exact on her family and extended relatives.

Anyone with information is asked to contact the FBI at 1-800-CALL-FBI. Anonymous tips can also be submitted to Tucson's Crime Stoppers affiliate, 88-Crime, at 1-520-882-7463.