Screaming or howling in St. Louis County, Minnesota

I was deer hunting about 5 miles from floodwood mn on co. rd 8 about a half mile after the blacktop ends just past the powerlines and before the gravel pit. I have hunted this state land for about 10 years with several friends and family over that time and knew everything about this area. On this Tuesday afternoon it was a very calm day almost no wind at all. You could hear every noise in the woods that day. There was not a deer in sight that day. I was going to wait till 5 or so and make my way out of the woods I had to walk through a couple thick cedar swamps on my way back to my car. At about 4:45 a branch snapped, then another. These were not small branches breaking and I could tell whatever it was was coming my way. I got my 308 ready to see what was coming towards me. I have been putting some bait out so I thought it might be a bear by how clumsily it was coming through the swamp. I then saw movement off my left side I got my gun up and tried to get the animal into my scope to identify what it's was. The color was dark brown like a moose and as I tried to get a good look at it through my scope. It stopped about 30 yards away and silence. I looked around my scope at it and I could not identify what it was. It was like a gorilla on two legs very thick and long hair. It must of saw me look around my scope. It was only there for a couple seconds and it let out a super loud howel. A howel like I have never heard anything make before. At that point it turned and went back the way it came from very rapidly. Covering ground through a thick swamp breaking branches as it went. I would estimate it went 100 yards in 10 seconds and then it stopped and howled once again very loud and it started moving again. I could tell it was going away from me to the south west rapidly. My heart was pounding through my chest. I climbed out of my stand and ran to my car about a mile away through that cedar swamp with my safety off and to scared to look back. I got to my car jumped in and tried to explain in my head what just happened. Until that day I was a avid hunter of everything and never thought there was a thing like this out there and now seeing and hearing whatever that was I quit hunting have not been in the woods much since, and never near there at dark.