A Twitter Event covering the recent attack on the Proud Boys march contains this text:

White nationalists and counter-protesters clash violently in Kalamazoo
Counter-protesters showed up to the site of an organized white nationalist rally in Kalamazoo, Michigan, on Saturday. When the white nationalist group arrived, violence broke out. Police responded to the violence, made arrests and cleared the crowd.

A "Rally" is a public meeting to hold speeches, and a "march" is, in this case, a number of people carrying flags. What antifa "counterprotesters" do is show up at a peaceful march like that and beat people up. See Charlottesville, Trump rallies in 2016, and the Greensboro "Massacre" of 1975.

Here are a couple of videos from local pro-antifa video guy Samuel J. Robinson:

Hell has broken loose pic.twitter.com/SBj5GqdhFq

— Sam Robinson (@samueljrob) August 15, 2020

Hell "has broken out" means antifa attacked, the famous passive voice. The Proud Boys defend themselves using non-lethal pepper spray:

Can't load tweet https://twitter.com/samueljrob/status/1294690720184438789: Sorry, you are not authorized to see this status.

Another "broken out" tweet:

Fights broke out between protesters and the Proud Boys group when they arrived in Kalamazoo. @wwmtnews pic.twitter.com/bgk0LGa6j7

— Trisha McCauley (@TrishaMTweets) August 15, 2020

It's one more event in the MSM progression from a free press to an Enemy of the People.