One of my Bro's was Army Recon in Viet Nam circa;1970. He told me about one night they were out on a mission in the jungle mountains. A few miles away, another squad was also on a mission.
They heard, yelling & full auto, off in the distance. When they got back to base camp. They learned the other squad was attacked by a large up-right hairy creature. One Veteran was physically attacked & bitten on the upper shoulder area.
The other's in that squad, scared the creature away during the attack.
Days later in the same area, while on another mission. By their camp site @ night. A large creature was roaring at them & throwing pieces of broken off tree limbs. At them in the darkness. He said, it sounded like a gorilla like creature. But when the creature roared, they could tell it was high up off the ground. As being, a very tall creature.