This... I find disturbing on many levels.
So this guy helps a lady being mugged (level of disturbing 1: the city has a low crime rate per capita so things like this tarnish those stats) and the Samaritan gets stabbed. The mugger flees. Apparently so does the lady (level of disturbing 2: some dude helps you out, gets hurt in the process and you walk away?). Then the samaritan falls down and is ignored for an hour, allowing the guy to freakin' bleed to death (level of disturbing 3 through 10: people PASS HIM BY during that hour and do nothing. Level of disturbing 100: some idiot takes out his cell and TAKES A PICTURE and walks on by). By the time EMTs arrive, it's too late.
So the guy was homeless. He helped someone and that is what he got? A likely slow death? Humans are so...!!!! I just can't believe it. Lady who was mugged, you know who you are, and your part in his death. A little gratitude in this case could have saved his life. And dude with the cell phone picture? I sincerely hope you share it and get caught and charged with accessory to manslaughter or something like that.
Sometimes, I really despise people.
I think I'm going to go look at cute kitten videos for a while.