Footsteps in Yavapai County, Arizona

My 15 year old son, my friend and I were out frog gigging in a creek off of rd 179 near Sedona and I-17 in Az. This took place on 06-29-2014 at 1240 am. We entered the creek which is knownas beaver creek. We all had our gigs and 100 lumen lights. And were walking up stream after we entered the canyon in which the creek was located. As we entered the canyon I noticed a wrong musky, stinky smell, but I did not say anything because this could have been skunk or javelin which is common in the area. After walking for about 200 yards, my son who was in front stopped and said he heard something walking away from him up the creek. I asked if it was a deer or elk. He told me he could not see because of the under brush, but said it sound like a heavy person. We continued for a few more feet and we all then observed three large rocks thrown from the thick brush above are heads, about 20 yards in front of us over the creek to the opposite side. We all stopped and then heard branches crashing as something crossed the creek in front of us. We looked in all direction with our lights but the brush and trees were too thick to see. I stopped and hit my gig against a tree three times. We then heard branches breaking up stream. We then crossed the creek and stopped. A rock was then thrown toward us and landed in the creek 5 yards in front of us. I advised my son and my friend we need to go, but as we turned to go back out, something very large ran toward us from up the creek bottom in the thick bushes, breaking large branches. We searched with our lites but could not see anything. We then walked out and made it back to the truck.