Pima County Sheriff Chris Nanos says investigators are reviewing tens of thousands of video clips as they continue to investigate the suspected abduction of Nancy Guthrie, six months after she disappeared from her home in the Catalina Foothills near Tucson, Arizona. He said the volume of footage could yet provide further evidence and appealed for anyone with relevant information to come forward.

Guthrie, 84, is the mother of “Today” co-host Savannah Guthrie. The sheriff’s office has released two purported notes believed to be connected to the suspected kidnappers, while Nanos said investigators remain confident they are pursuing the right leads despite setbacks.