Sinister: True or False?

Recently I watched the 2012 movie Sinister. I hear that it's based on a true story, and that some of the footage from the movie is real footage taken from the scenes of the crimes. Baghool is terrifying, but I have a hard time believing it. Also, if Baghool was in the videos, who's carrying the camera to record him? Does Baghool have a partner? I guess we'll find out in the second.