I send in the 1 water canon swat teams as well as a few more swat teams. I use a couple of patrols to block of the streets as well as what they are facing (this makes them back up a little). I also have a fire truck and a large ambulance staged one block out in case someone gets hurt or they start a fire as well as 2 or 3 police vans (depending on how many there are). When everything is in place, I get a few guys with shields and the rest are just ready for arrests. I have them all start heading toward the protectors to start arresting while I throw a flash grenade. I then arrest a good 85% without any trouble. The rest are quickly caught and put in the police vans. This usually results in no injuries, but there sometimes are a few(1 or 2). If things get way out of hand, I try and get as many of my units out and behind the water canon as possible, start the water canon up and wait for backup.