Screaming or howling in Box Elder County, Utah

First encounter was east of Brigham City, Utah, above a place called upper docs flat. Had been hiking with a friend. His name is Kenny A. I do not wish to use his last name without his permission. We had been hiking all morning going higher and higher through the valleys, zigzagging back and forth. At one point we went up a spine or ridge, and at the top of this spine was an old cabin. I think it was referred to as the old sheep herders cabin. In front of the cabin was a small pond. Hiking our way towards the cabin I stopped at the pond. The water was clear and suitable for drinking, maybe fed by a natural spring. My friend started to cup his hands to drink, and did so. I started looking around the pond which had a smooth dirt skirting around it. I then asked Kenny if he noticed anything wrong with the pond, and he said no. I said, “look were you knelt—you left tracks.” I said, “do you see any other tracks around the pond?” At such a location there should be tracks everywhere, but there wasn’t—not even bird tracks. We also noticed that there were no sounds, birds, squirrels etc. Kenny was starting to get nervous at my finds. Although he was a friend, he didn’t have the outdoor curiosity that I do. After about 15 min., we decided to start heading back. About half way down the spine we had hiked up, Kenny heard grouse, or sage hens, in some pines and trees on the opposite side from where we were. He decided he wanted to hunt that side on the way down to the flats. I agreed and told him to stay opposite of me on the other side so we knew where each other was at in case he fired the shotgun. He agreed and I took the disassembled single shot shotgun that I had in my backpack put it together for him, gave him some shells, and told him I would stay in place till he was even with me on the other side. I sat and watched him descend to the bottom of the draw between the two spines. He was moving very slow and quiet. When he was ready to start up the other slope he encountered heavy brush with thorns that he had to get through. It was 7-8' and I could see him unsticking the branches of thorns that were catching his clothes as he made his way. I could see that he was almost out of the thorns. He leaped forward and must have had a branch snag his arm he screamed with pain. At that moment I heard a loud crash higher up than Kenny. It sounded like a 1-ton rock was dropped from the sky. I started scanning the area where it came from. Kenny was still making noise from his injury and didn’t hear what I heard. What I'm about to describe is something that I have never forgotten because of the impression it has left with me. Have any of you taken a large rock and dropped it in deep water the sound it makes is "thunk"? That’s what i heard—thunk,thunk,thunk—very fast. At this time my eyes are racing all over that hillside and then I saw it. It was about 400 yards above Kenny and running towards him. I'll admit my heart was in my throat. I started yelling at Kenny to get out of there, and kept repeating it at the top of my lungs. Kenny finally heard me and the noise coming towards him and ran through those thorns that he just went through. He was half way through the thorns and must have accidentally fired the shotgun. At that point I saw it stop and start running the other way, Kenny was already coming up on my side. When he reached me he was out of breath and bleeding all over from those thorns. Kenny was shaking and crying. I had to keep telling him that I saw it run away when he fired the shotgun. At that time I took my shotgun back. We all know that firearms are for responsible people, not those who are out of control. We made it back to our start point in record time and got the hell out of there. It took Kenny almost 2 weeks before he even wanted to talk about it, and when we did I described what I saw. I would say it was 7-8 feet tall, dark reddish-brown hair with a white cap. The distance was about 500-600 yards away and closer as it came towards Kenny. I'll never forget it. Kenny didn’t see it but heard it coming. He said he didn't feel the thorns until he was with me on the other side. Being from Brigham City we decided not to tell anyone because it was a small town, and who would have believed us?