he FBI has recovered additional imagery from cameras at the Arizona home of Nancy Guthrie, the missing mother of “Today” show host Savannah Guthrie, sources briefed on the investigation told ABC News.

Investigators were unable to recover video footage, but thumbnail images captured when the cameras were triggered by motion.

The cameras recorded nothing suspicious, the sources said.

Investigators were able to observe several people in the back and side yards over an unspecified period prior to the abduction. After Nancy Guthrie was taken, law enforcement officers are seen near the pool.

However, the cameras captured nothing on the night of the abduction, the sources said. Investigators have drawn no conclusions as to why, but one source described it as “odd.”

The Pima County Sheriff’s Department said Friday that it “continues to analyze various forms of evidence in the Nancy Guthrie case, including material from laboratories as well as images and videos captured by cameras.”

“At this time, we will not comment on the details or status of this analysis,” the statement continued.

Nancy Guthrie was taken from her Tucson-area home nearly seven weeks ago, in the early hours of Feb. 1.

The FBI has previously released photos and videos of an unknown armed suspect in front of Nancy Guthrie’s home on the morning of her disappearance, appearing to tamper with a security camera.

The masked man appears to have been at her front door earlier than Feb. 1, sources familiar with the investigation told ABC News.

Nancy Guthrie abduction: The full timeline

The Pima County sheriff has repeated this week that he believes Guthrie was targeted, but investigators have released no motive and have identified no suspect.

Savannah Guthrie has offered a $1 million reward, bringing the combined reward between the family and law enforcement to $1.2 million.

Anyone with information is urged to call 911, the FBI at 1-800-CALL-FBI, or the Pima County Sheriff’s Department at 520-351-4900.