There are 2 versions -- the one on the original site is missing some time -- if you follow the time index on it it jumps between when they jump on him and when he is on the ground. In that video the screaming starts before the actual act occurs. That part is cut in the video but not in the audio -- after that they just chant to the moon good so you can't tie it to the action.
Bottom line, these are sub-human gutless evil cowards who will have to face the real God someday -- and hopefully the USA can hasten that day.