What to do when officers arrive on scene

So i had a random thought. Let's say there is a situation in a public building where a guy has a gun, you intervene and you subdue him but you keep your gun on him cause he is still conscious and can move. You tell someone to call 911.Once you have word that the police are about to walk into the building, what should you do? Hold up your hands? Holster the gun? Make it verbal that you're not the hostel one? via /r/CCW http://ift.tt/28TnlgF