The disappearance of Nancy Guthrie continues to baffle investigators months after she vanished from her Arizona home. 

The 84-year-old mother of Today show host Savannah Guthrie was abducted from her $1 million Tucson residence in the early hours of February 1.

No suspects have been named and there have been no arrests in the lengthy investigation.

As the Guthrie family continues to beg for information leading to their mother's return, investigators are forensically analyzing terrifying footage which showed a masked man on her porch the night she disappeared.

The black-and-white video shows a gloved individual tampering with her Nest doorbell camera shortly before it was disconnected at 1.47am on February 1.

The suspect appeared armed and was observed tinkering with a security camera mounted near the entrance.

The nightmarish footage was released on the tenth day of the hunt after it was recovered from a backend system.

It took investigators several days to access because Nancy did not have a Nest subscription, which would have uploaded the images and saved them to a cloud storage platform.

Pima County Sheriff Chris Nanos had previously said no footage was available because Nancy did not have a subscription to Google's video storage service, which typically keeps recorded clips in the cloud. 

The FBI managed to obtain the doorbell camera footage days by accessing residual data stored on backend servers.

Additional video released by officials showed the individual attempting to cover the lens with a clenched fist, then searching the area around the door, ripping a bunch of flowers from the entranceway and waving them at the camera.

Another clip shared by the FBI showed the individual hunched over as they made their first approach to the door, bowing their head.

Authorities believe Nancy was kidnapped, abducted or otherwise taken against her will after finding blood near her front doorstep.

The Guthrie family is offering a reward of up to $1 million for information leading to Nancy's recovery.

 Savannah Guthrie made an emotional plea on Tuesday's Today show for more help in the search to find her missing mother, Nancy. 

Guthrie kept a brave face as she urged people to come forward with information on the case, crying at points after reporter Liz Kreutz recounted new details in the case. 

On Monday, it was revealed a ransom note the family received in February said the senior was dead. 

The Today team played a clip Guthrie and her sibling posted the following day to Instagram. 'We beg you now to return our mother to us, so that we can celebrate with her,' Guthrie said at the time. 'This is the only way we will have peace. This is very valuable to us, and we will pay.' 

A clip of Guthrie's March conversation with former co-anchor Hoda Kotb was also played. 

In it, Guthrie said, despite a flow of fakes, she suspected the 'two ransom notes [the family] received and responded to' in February were authentic Kreutz emphasized that the 'new' details did not serve as a major 'update', leaving Guthrie to react.

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