To me it totally looks like the protesters got scared and locked arms, running towards the police line because they wanted help (because something scared them).

I'm sure the bikers at the back who were forming a perimeter with their bike lines (some of the ones who are complaining about having their bikes taken) we're merely trying to hold the ground, ready to clear it in moments notice in case back up police arrived to render additional help and aid the protesters.

Unfortunately for the protesters, the police didn't react well, even in the face of being offered free umbrellas and sticks. Instead of helping the protesters like they wanted, the police planted someone in the crowd to WWE style pretend to smack a cop over the head with a skateboard as a pretext for an all-out melee.