Authorities released a photo and sketch of the unidentified man.
They said he is seen in a video with a child who is part of that investigation.
The FBI believes this man may have critical information about the child's identity.
The man is described as a white male, 30 to 40 years old, heavyset with dark-colored hair. The FBI said he can be heard speaking English in the video.
If you have any information about this man, contact the FBI at 1-800-CALL-FBI (1-800-225-5324) or at tips.fbi.gov
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