A bridge, a body, what happened? (see details)

You are walking back to friend’s house where you have been staying, to get back to their house you had to cross a foot bridge 12 feet over a frozen creek. You are enjoying the still quiet. On the way back you see a person laying face down in the middle of the bridge at the crest. Upon approaching the body you see lots of red snow on the ground around his skull and a small hole in his head; there is nothing near by or under the body just the fallen man. The snow had been falling so there was a good 2 inches on the ground wiping out all old footprints even your prints when you 1st crossed the bridge. The only footprints are the person lying face down and yours both walking to the crest of the bridge. A small patch of snow on the rail has been brushed clear and there is a deep scratch in the wood. Below the scratch and clear space on the rail is a basketball sized hole in the ice below covering the creek. So, what happened?