I'm curious to know who shot whom in this melee and how many were killed by police, who may well have been fully justified in doing so. Just don't know at this time. Police are kind of in a rock and hard place situation. Having probable cause sufficient to make an arrest stick and withstand an expensive lawsuit if it doesn't is likely to be problematic. The same tactics and legal construction that police might have employed to preemptively stop the violence are probably going to turn out to be the same tactics and legal construction that would allow police to "preemptively" round up a bunch of open carriers having dinner. Having been on the receiving end of police misconduct (the Tony's 7 incident in 2007 - nobody got shot or arrested, just forced to leave) I wouldn't be happy giving police a blank check to break up, disperse or arrest a group they didn't like or feared were capable of mischief. The probable cause bar is set high for a reason. Until you actually do something illegal, you shouldn't be subject to harassment just because you could do something illegal.
I hope there's some video both inside and outside the restaurant. I'd sure like to know how all this shooting got started.