There is a video going around of the shooting, taken by the two shooters. I will describe what is noticeable in the videos. Do not read this thread if you are not compatible with descriptions of gore or violence.

https://twitter.com/syriansaracen/status/2056597971102585220

The two shooters livestreamed the attack on Discord. A viewer recorded it from another device, then started another livestream, also on Discord, and the person viewing that second stream screen recorded the second livestream. I will not be posting the video out of respect for the