The masked man who appeared on Nancy Guthrie's doorbell camera on Feb. 1, the night she disappeared, had been there before, a source close to 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 on a day before the suspected abduction, according to sources familiar with the investigation.
The image shows what appears to be the same man dressed identically, but without a backpack and a gun in a holster.

ABC News said the FBI and the Pima County Sheriff's Department declined to comment.
The gap could explain why investigators are asking neighbors to check their home security systems for suspicious people and vehicles going back to Jan. 1, a month before the abduction.