Hey guys, here's a lesson. If someone asks you to leave their property, just fucking leave it. Street skating is fun, but they do have a moral high ground. You could mess up their property, and many are afraid (though I doubt most street skaters would try to do this) that if you fall and hurt yourself, you could sue them. Being sued is a property owner's worst nightmare. Next time someone tells you to leave a spot, just fucking leave and come back later. It will always end up better for both parties that way.
As for these guys, same rules apply. I don't care if the security guard started it, because that was his job. The skaters should have just left right then, if the security guard came after them they could have easily outran him on their boards. And hell, if the guard leaves the property and somehow catches up to them, then tries to attack them again, then the skaters have every legal right to kick his ass. But that's not what happened. They ruined a man's life, and that is not acceptable. It makes every skater look bad.