Seems as though there is probably more to this story.
I mean according to the story I read from the Bankok news articles (on the internet) he was in Thialand filming a movie at the time.
I'm not sure that a working actor would commit such an act as suicide unless he was on drugs or out of his mind on something. Since Mr Carradine was 72 I kinda of doubt that.
I think the authorities shouldn't dismiss this so quickly as a suicide.
I might be wrong, but It just sound fishy to me.