Did you read all of that?
It's way easier for the police to focus on the main mass of protesters than those who split off and go commit crimes. Especially when manpower and other resources are limited. What I get out of that story is that the cops are either outmanned and in a difficult position, or they've been incompetent, or perhaps some degree of each. Evidence of cops violently beating protesters not seen here. This is the meat of your "police riot" claim:
But that's a small part of a larger article, and different people are saying different things about police conduct there. Some are saying they are being restrained. Some are saying they aren't aggressive enough. When the dust settles, the best indicator will be how many deaths or serious injuries come out of this. For now, none of either have been identified.
If the riots go on, I'm sure we'll see some more police violence. Possibly much worse than what is described there. There's a lot of cops out there because there's a lot of rioters out there. Just like not all the rioters are good people, not all the cops are either. It's inevitable, especially the longer and longer it goes on.
Do you honestly expect violent rioting to go on for 6 days across the nation and no one gets hurt? Even with the most restrained possible response, and I'm this isn't always as restrained as it should be, harm to people is inevitable. None of this convinces me that this rioting is a good thing.