The person who posted this clip says that the footage was shot by an elderly man out walking with his dog. If it is a CGI effect, it's a very good job. It is difficult to get movement like that behind trees, but certainly not impossible. In any case, the poster is adament that it is not a hoax. As part of our new professional grade evaulation program, we intend to interview this witness and analyze the video. Once this is done, the video, the interivew and the analysis will be posted.