Does anyone know what really happened to SSGT John H. Turner

Non-Hostile, ground casualty other accident is how they have described John's death. Later we heard that he was shot by his own men. Does any one know where quang nam is? Is it Da-Nang. John was in an - E6 Regular Army MACV Advisors. No one really tell us what happened. After all these years there won't be a judgment, but details seems to dilute the imagination. He was killed on May 20, 1968.

I rememeber his last words to me were " I need to go back again because there are so many young kids that need the training that I can give them so that they can stay alive."

Can anyone help me!