I live in a part of the world where there are many coyotes, some of them with rabies. I can't recall ever hearing of a fatal attack on a human by coyotes; they are generally timid and elusive. I have heard of cases where people have been bitten by rabid coyotes but I have never heard of a fatal attack. There are, however, quite a few documented cases of fatal attacks on humans by feral dogs. Not just in Arizona but throughout North America.
Since in this particular instance the attacking animals were never seen, other than by the victim, I wonder whether feral dogs might have been to blame. I know that I have had some scary encounters with dog packs.