Donna,

I did a quick search in the material I have concerning  SGT Robert E. Cannon and the best I can come up with is a page from the 1st Infantry Division History book for the year 1968. I have scanned the page and put it on this tread. From the casualty list for the 1st Battalion, 2d Infantry he was the only loss during that period. There is nothing specific as to what he was killed. Hope this bit of information is at least a little helpful.

L R Grzywinski
Historian
2d Inf Regt Assn