Report 42295: Possible encounter makes campers leave Lake Jeanette campground near Orr

Went camping at Lake Jeanette in the Superior National Forest in Minnesota. First night we were there we heard wood knocking. Knocked back and got three distinctive and separate responses. As we started to go to bed we heard a whooping noise. The next day we hiked out into the area which the sounds came from; no camps, nothing out there. After a long day of hiking and and swimming we went back to camp, ate dinner, and that night we started the knocks. Again we hear three responses. One of the three got closer and closer after each time we responded back. My friend got creeped out and we left the woods and sat at our camp site. As we are sitting by out fire we both saw a set of eyes staring at us. Neither one of us said anything about the eyes to the other until we were on our way home. We decided to go back into the woods for one last time and as we did something very close to us made a loud grunt. I've hunted since I was 12, I have heard bears, moose and everything else that would be in the woods of Minnesota and I have no idea what this was. We took down our tent and left within 20 minutes of this grunt. I don't know what was there but we both felt like it didn't want us there.