Paint ball loaded with blue leather dye and itching powder.
Not bad. We could have fun with this.
But this is Arizona. Why not just a few guys off in the nearby hills emptying a bunch of magazines into the dirt or better yet, some periodic deer rifle shots.
These little babies despise guns. The sounds of gunfire should scatter the majority, the cracks of hunting rifles will have them sweating and wondering if chaining themselves to their vehicle is really that fun. For added effect: harmless laser dots on their chest coupled with psychological warfare by blasting patriotic music or maybe a Hillary screech tape.
My favorite though, and the quickest way to get them out of there is to let a few good ol' boys empty a few bags of rattlesnakes and bark scorpions onto the pavement right next to them ( they're greenies, and they DO want to save these critters ). Of course you would have to first bag or jam the media cameras and cellphones so that the area goes dark temporarily.
Doing something like that would result in them sawing their own arms off faster than the deputies could ever bolt-cut their chains. They'd probably saw the wrong limb off!
Come to think of it, we would definitely want at least one camera recoding this for entertainment purposes!