I'm sure you were innocent, unfortunately it's nothing new, about 20 years ago I took a diversion on the way home from the pub with my girlfriend to buy some fags from the garage, once I was on the ground I was kicked in the head half a dozen times, and informed it was because "we fuckin' hate you" before the three of them walked off. So yes, sometimes you're just in the wrong place at the wrong time. The ambulance crew were lovely though!