Report 4159: Campers hear unusual grunting sound from behind tent

During the deer hunting season of Nov., 1995 we (my brother, son, and friend) were just getting into our sleeping bags to get a nights rest before our deer hunt the next morning, when a strange sound came from behind my son's tent. It was unlike anything we'd ever hear before in the forest. It was an animal with a deep barreled grunt, and making a shuffling noise as it moved behind the tent. Being an experienced, 50 year old hunter and my brother with even more back-woods experience having heard the noise got up with deer rifles and lights and went to investigate. The animal left the area very quickly, making a loud grunting sound and knocking down heavy brush as it left. We never saw a thing, but it was something we could not identify or explain. We even stayed at camp the next morning to look for sign or tracks to identify the creature. We found nothing, not even a track. Locals say there's a creature in this area (Trinity County, Texas) they call "the Gray Thing". Well we never saw what color it was but I can safely say it was something out of the ordinary. We don't drink liquor, and as a Christian, I don't lie. We will go to our graves wondering what came to our camp that night.