Gosh- I did read about this many years ago in a book about prisoners of war. AFAIK the prisoners were working in some underground mine and one of the prisoners had a violent disagreement with another and hit him with a shovel and chopped his head off. He was being moved to a different camp- not for beheading the other guy, but because he did not want to then remove the head.
I can’t recall the book but it may strike a chord with someone.
I have an army surplus folding shovel in my car trunk - 1st thing I noticed when buying is the blade - not only tapered with an edge, but serrated! They Army definitely intends for dual use as a weapon - the little tag says it’s also good for chopping thru wire.
I could swear remembering reading a story of Charles Durning, who is a WW2 vet, that he was in hand-to-hand combat, and took (or almost took) a German soldier’s head off by swinging his shovel.