Suspect.
I bet the suspect already has a Fan Page on Facebook.
That beard looks kinda muzzy to me.
I am going to be a little contrarian - this guy maybe a shooter - but the news is reporting multiple gunmen that were shooting from a high position and this guy is street level. He could be someone who showed up with a rifle to make a protest point and not the part of the shooting.
With that said, he should be found.