Untitled Sighting

myself and 2 friends were fishing from a boat on moose lake mn. in sept of 1993 we were roughly 100 ft offshore when we passed a small point of land sticking out into the lake.at that time we heard a loud screaming noise come from the treeline just past the point.we were stunned by the volume and tone of the noise.it seemed like we had disturbed something when it had come down to drink at the lake.after hearing the scream,we heard the sound of branchs breaking and what i thought were bipedal footsteps it made a different sound then say a deer crashing thru the woods to get away.the 1st thing i thought was 'so that what a banshee scream sounds like'.it sounded almost like a woman screaming.the shore/beach where we heard this is about 20 ft deep then gos uphill rather steeply.after we heard the sound of it running away to the top of the hill it screamed again!! i had always heard about the hair on the back of your neck standing up,well mine sure did! one of my friends thought it sounded like a bird. i asked him did you ever hear a bird break branchs like that?we then proceded to the lanch ramp and left in a hurry! i have heard and seen about every kind of animal in north america but i never heard anything like this.i guess i should note we saw nothing just heard this scream. thank you