Now that they have closed the case, Wyoming police are releasing details about the murders of Charles Oppenneer, his pregnant girlfriend Brooke Slocum and the suicide of killer Brady Oestrike.

Of particular interest is the first report of suspicious activity in Gezon Park during the early morning hours of July 13, 2014.

Austin Schuur says he and girlfriend Hannah Reardon were in his parked car talking and listening to the rain when Hannah was surprised to see someone peering in through the rear window.

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“I actually punched the window,” recalls Austin. “And to my surprise it ended up being a person wearing a white mask in a hoodie. He stood up and walked to a car about 20 feet away. We got scared and drove off.”

But the couple stopped at a Wyoming police car along the way and reported what happened.

While looking for the peeper, the officer noticed the abandoned car registered to Charles Oppenneer.

He came back every day and when it was still there three days later, they searched and found Oppenneer’s decapitated remains in the nearby woods.

“The guy who looked in our car was more than likely a creeper,” speculates Schuur. “But he played a factor in that night because if we didn't have him we would have never gone to authorities to report anything weird going on back there in the first place.”