See the News Article, Video, Photo Gallery.
Now this is bizarre. A man walks down a street in Cardiff (Wales, UK) in only his underpants, smashing store windows with a shovel.
In the video, there's a pedestrian, apparently unperturbed by the scene, who walks right by the pants vandal. Actually, I think that's the right thing to do in such a situation. Get a safe distance away as quickly as possible without drawing too much attention to yourself. Let the professionals pants him. After all, you wouldn't want to get clobbered in the head by a crazy almost-naked man.