On the Building. Direct Line of Sight. It's Incomprehensible

I have been doing an AAR in my head since everything went down. I could tell that the shooter was close, less than 200 meters by the sound of the shot & then the crack of the bullet over our position. I didn't know exactly where the shots were coming from, but in the chaos of the moment & based on the trajectory of the round, I thought water tower or the rooftop of the building.