A chilling ransom note demanding millions of dollars for the safe return of missing Arizona grandmother Nancy Guthrie set a 5 p.m. Thursday deadline, federal authorities revealed during a tense press briefing — though investigators stressed the message has not been confirmed as legitimate, per the Daily Mail.

Officials said the letter, which allegedly called for payment in Bitcoin, contained no proof of life and offered no clear way for the Guthrie family to communicate with whoever sent it. Despite those red flags, the FBI said the threat is being taken “very seriously” as detectives race against time to locate the 84-year-old.

Pima County Sheriff Chris Nanos also disclosed alarming new details about Guthrie’s home surveillance system. A doorbell camera disconnected at 1:47 a.m. Sunday — hours before she was reported missing — yet motion sensors later detected a person near the property at 2:12 a.m. Moments later, at 2:28 a.m., data showed Guthrie’s pacemaker app suddenly lost its Bluetooth connection to her phone, marking a critical point in the timeline.

Investigators said no suspects or persons of interest have been publicly identified, but Nanos warned that “nobody has been ruled out” as detectives pursue every lead. Authorities also clarified that a carefully worded statement about Guthrie’s condition was not meant to suggest she had died, emphasizing that the search continues under the belief she could still be alive.

Nanos started the press conference by saying : “We believe Nancy is still out there… We want her home.”

Sheriff Chris Nanos said that while no suspects have been publicly identified, the FBI arrested an alleged impostor early Thursday who is accused of sending a fake ransom note connected to Nancy Guthrie’s disappearance.

New images from outside Nancy’s home also revealed a trail of blood leading from her front door to the driveway, and investigators confirmed that her doorbell camera had been removed. During Thursday’s press conference, officials said DNA testing showed the blood belonged to Nancy, though no other forensic evidence has pointed to a suspect.

FBI Special Agent Heith Janke said investigators are leaving no stone unturned, analyzing digital records from banks, social media platforms, phone companies and other sources that could reveal a digital trail.

Authorities confirmed they received a ransom note sent to TMZ and local outlet KOLD on Tuesday, three days after the 84-year-old vanished from her home. The letter — which has not been verified as legitimate — reportedly demanded millions in Bitcoin and included detailed information about what Nancy was wearing when she disappeared. Officials said they are investigating every lead but have not confirmed the note came from her alleged abductors.

Meanwhile, Arizona news anchor Mary Coleman said she believes the message “might not be a hoax,” noting that parts of the email contained information that appeared highly specific. Savannah Guthrie referenced the note in an emotional plea for her mother’s safe return, saying the family would need proof of life before considering any demands. Coleman added that the email was immediately turned over to the Pima County Sheriff’s Department after it was received by the KOLD newsroom.