July 3 (UPI) — A California man has pleaded guilty to sending phony ransom requests to the family of Nancy Guthrie, the mother of Today host Savannah Guthrie, who has been missing for five months, federal prosecutors said.

Authorities have been investigating the disappearance of Nancy Guthrie as a kidnapping and ransom scheme since she was reported missing from her Arizona home on Feb. 1.

In his plea deal, announced Thursday, 42-year-old Derrick Callella of Hawthorne, Calif., admitted to calling and texting a demand for a bitcoin transfer to a member of Nancy Guthrie’s family on Feb. 4, while acknowledging that he knew there had been an earlier ransom demand.

He also admitted that he meant to harass the family by seeking information about the 84-year-old woman and the investigation into her disappearance.

Authorities have said that Callella is not connected to the disappearance of Nancy Guthrie.

After Nancy Guthrie went missing, her adult children, including Savannah Guthrie, posted a video to social media urging the kidnappers to contact them.

According to the complaint, not long after the video was published, two people identified in the document as A.C. and A.C.’s husband, T.C., who are believed to be Annie Guthrie, one of Nancy Guthrie’s daughters, and Tommaso Cioni, separately received text messages, stating: “Did you get the bitcoin were [sic] waiting on our end for the transaction.”

Authorities said the messages were sent with the use of voice-over-Internet-protocol and a smartphone application that allows users to obtain a separate phone number for the device other than the one they were assigned.

Despite the efforts to obfuscate the origin of the text messages, authorities were able to trace the messages back to Callella in California, the complaint states.

The FBI arrested Callella a day after the text messages were sent.

When sentenced, Callella faces up to a maximum penalty of two years’ imprisonment and a fine of $250,000 for each of the two counts of harassment using a telecommunications devices he pleaded guilty to.

Callella pleaded guilty amid renewed interest into the case following reports stating authorities believe notes from the purported kidnappers claiming Nancy Guthrie had died were legitimate.

On Wednesday, the FBI’s Phoenix field office appeared to be undercutting those reports, issuing a statement stating that some of the ransom notes they have received over the course of their investigation have not been legitimate.