A slit across the neck just below the jawline, where the chin meets the neck, with the victim's tongue hanging down through the wound.
They would slash their throat and then pull their toungue out from the open wound.
This was a manner of psychological warfare to scare the living shit out of any people who would discover the body.
man 2- Im going to vomit
Should stop your tongue from wagging the dog
No more stupidity from you, as I pull your tongue through
For a smile from ear to ear, now there's nothing to hear
-"Sleepwalker" by Megadeth