What a tragic event. My thoughts are with the family and those of you who live in the area.
Was this an area that someone could only get to by bike or foot? Would the perpetrator likely have been on a bike too? I usually assume that criminals are too lazy or out of shape on unskilled to commit crimes more than about a mile from a road. This rule seem to work pretty well for hiking and backpacking. Areas frequented by locals or accessible by car or ATV are considered unsafe for overnight stays by hikers. So is anyplace a road bike can get to potentially unsafe if not in a well-populated area?
