I just wanted to post a link to a video that a jogger recorded while a (Black?) bear was following/chasing him all the way to his car. The bear is within arm reach of him.
This could easily happen to hikers.
http://www.cnn.com/video/data/2.0/vi...ggers.ctv.html
(I spent 1 night on the A.T. and in the morning there was a black bear 3minutes after I broke camp, so I do know that although not too common, bear interactions do happen. Be prepared)