I forget the name of the victim but Anneillo Dellacroce once beat a man tied to a chair to death with a mallet hammer. When the cops found the body they initially thought the man had been decapitated and the head was missing. It was during the autopsy it was discovered the smashed in skull had been beaten down into the chest cavity. This was in the mid 50's.
I read about this in a book called Gangland International by James Morton. It was quoted by the detective who investigated Dellacroce for the murder but is the only time I've ever seen any info on this killing.