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This is a video from the concert that caught flashes coming from the 4th floor....
The shots in the video were going on when the shots were heard....
The noise is off by a little bit but the distance fits the delay....
Watch and you be the judge....
Not saying it's a false flag until more news comes out but someone caught this on video and it's worth a look....

Regardless....my condolences to those who lost their lives.