TUCSON, AZ — The masked man who is suspected of the abduction of Nancy Guthrie appears to have been at her front door before the night police believe she was kidnapped, sources familiar with the investigation told ABC News.
The image the FBI released of the suspect at her front door, without a backpack, was captured by her Nest doorbell camera before the suspected abduction, the sources said.
See previous coverage surrounding the search for Nancy Guthrie in the player above.
The FBI said the images of the suspect with the backpack on are from “the morning of her disappearance,” Sunday, Feb. 1, when Guthrie failed to show up to watch a virtual church service.
One theory, according to the sources, is that the suspect approached the door the first time, noticed the camera, and was scared off, only to return later, when he is seen tampering with the device and putting branches in front of the lens.
The FBI declined to comment and the Pima County Sheriff's Department released the following statement Monday, refuting the report:
"We are aware that doorbell images released earlier in the investigation depict a suspect in different stages of attire, including with and without a backpack.
There is no date or time stamp associated with these images. Therefore, any suggestion that the photographs were taken on different days is purely speculative.
This remains an active and ongoing criminal investigation. As with any investigation, conclusions will be guided by verifiable evidence and established facts. Speculation, without factual support, does not advance the investigative process."
FULL COVERAGE: The search for Nancy Guthrie
Investigators have asked neighbors to check their home security systems for suspicious people and vehicles going back to Jan. 1, a month before the abduction.
The images are the most important pieces of evidence in the investigation into "Today" show host Savannah Guthrie's mother's disappearance, which has captured the attention of the nation for much of the last month.
WATCH: Investigators analyzing biological evidence found at Nancy Guthrie’s home
Earlier this month, Pima County Sheriff Chris Nanos sat down with ABC15 to discuss the latest on the Guthrie case. Hear from him in the player below.
So far, no suspect has been identified by officials in Nancy Guthrie's disappearance.
Jason Pack, a former FBI agent, told ABC News that if it is the same person, "it could indicate that the person was there surveilling the place before the abduction happened."
TIMELINE: What we know about the events surrounding Nancy Guthrie's disappearance
"The fact that there was preparation and planning, which makes it more of a sophisticated type of criminal activity than someone just showing up," he said.
