Do they know why the body was burned or any idea who it was? I saw a really interesting show on spontaneous combustion once. A person was found completely burned to a cinder in their home. They burned to death on their couch, yet oddly enough nothing else in the house caught fire. It was just all sooty around the corpse.
The makers of the show were curious why that was. One of their experiments was with a really huge pig they bought at the butcher shop, doused in gasoline and set it on fire in a simulated bedroom. The pig burned for about 14 hours and reached temperatures to I think about 600 degrees. Nothing else caught fire in the room though. Not the carpet, or the bed or dresser. However, the tv did get extremely warped.
But that burned body by your home was probably a homicide. And I'm sure you're thinking, "Well duh!" Nevertheless, that would really weird me out if that happened to close to me. So my heart sincerely goes out to you man.