The FBI and the Pima County Sheriff’s Department are “aware of a new message regarding Nancy Guthrie,” the sheriff’s office said Friday.

“Investigators are actively inspecting the information provided in the message for its authenticity,” a social media post on Friday from the sheriff’s department said.

Nancy Guthrie, the 84-year-old mother of “Today” show host Savannah Guthrie went missing last weekend, and authorities have said they believe she was abducted from her Arizona home.

Earlier this week, authorities said they were reviewing possible earlier ransom notes.

The FBI, which announced Thursday it is jointly investigating the case, is offering a $50,000 reward for information leading to the recovery of Nancy Guthrie and/or the arrest and conviction of anyone involved in her disappearance.

“While this is one new piece of information, the FBI and the Pima County Sheriff’s Department are still asking anyone with tips to contact the FBI at 1-800-CALL-FBI,” the social media post stated.

Authorities didn’t say what the message said, but sources told ABC News a note was sent to a local media outlet and that it is being taken seriously by law enforcement.

Nancy Guthrie was last seen at her home in the Catalina Foothills area, north of Tucson, on Saturday night, according to the Pima County Sheriff’s Department. She was dropped off home shortly before 10 p.m. after having dinner with her family, he said. Her family reported her missing on Sunday around noon local time after she failed to show up to church, authorities said.

A doorbell camera at her home was disconnected at about 1:45 a.m. Sunday morning, and shortly before 2:30 a.m. Nancy Guthrie’s pacemaker app indicated it was disconnected from her phone, authorities said Thursday during a news conference in which they laid out a more detailed timeline into her disappearance.

Nancy Guthrie’s blood was found on the porch of her home, the sheriff also said.

No suspect or person of interest has been identified in the case, Pima County Sheriff Chris Nanos said during that press briefing Thursday.

“Right now, we believe Nancy is still out there,” Nanos said. “We want her home.”

Regarding the past ransom notes, which were sent to several local and national media outlets, an FBI official told reporters on Thursday that investigators are taking them seriously.

Savannah Guthrie and her siblings made an emotional plea for their mother’s return in the video message posted to social media earlier this week.

In another video posted on Thursday, Savannah Guthrie’s brother, Camron Guthrie, directed his statements toward his mother’s potential kidnappers, urging them to reach out and prove they have her.

“Whoever is out there holding our mother, we want to hear from you,” Camron Guthrie said in the video. “We haven’t heard anything directly. We need you to reach out and we need a way to communicate with you so we can move forward.”

He closed the brief message saying, “We want to talk to you, and we are waiting for  contact.”