Ok, there were more signs than that, whether when still alive or not. Attitude, appetite, gait prior to death? Weather? Position of body, location, POST MORTEM FINEDINGS etc after death?
The list of possibilities includes anthrax, anerysm (gosh that just doesn't look right but I'm tired...) gunshot, liver failure, lightning and a whole lot more!
The most important thing to do with a sudden death is to find out why. The best source of information is the body with the answers to the questions I have just asked being a good second. Get a PM!