is the mayor still on the phone, mayor doug -- i think the mayor had to go back -- and jim kavanaugh, former fbi negotiator, jim, tell us now how do they determine just what the response should be and whether or not there's any way of negotiating or finding out who this person is and presumably it's only one person. >> right, andrea. the protocol is to locate, isolate and then evacuate. they are going to try to locate the shooter and isolate him in this same moments and also trying to evacuate people. if students have locked themselves down, police will try to push the shooter into a certain room location where it's only him. you know, they've got to get him stopped and isolated before there can be any negotiation. an active shooter is not a person who wants to negotiate. he's a person who wants to kill. and we know this from all of these events that have gone on. we also know that police are very effective in engaging them and stopping the carnage. so you saw just this week in the shooting at the police officers in las vegas where when the officers arrived, the two teams immediately