The ones who need to be targeted first are in the shadows choreographing the riots. Those are the hard core communists running the show. You will rarely see them on the street brawling alongside their brainwashed street goons. They are a block or two away, tucked away safe. Voicing orders from a safe distance.
Okay. Them too.
Yep. This was very organized. Somebody had to tail the principals, locate where they were eating, and call in the thugs. Probably used a text page to a pre-arranged address, who then distributed it to a pre-arranged list. Or through a secure web page. Tough but not impossible to trace. From there to assassination is a very small step.