evacuation from afghanistan. >> in the days remaining, we believe we have the wherewithal to get out the american citizens who want to leave kabul. >> reporter: taliban warning there will be consequences if it takes any longer. a firefight at the airport sunday that left one afghan security member dead underscoring the tense security situation as the u.s. tries to maximize the number of people it can fly out. >> we are pushing the limits to do everything we can to get every single evacuee out of kabul. >> reporter: in order to speed up evacuations, the pentagon activating the civil reserve air fleet for only the third time, using 18 aircraft from commercial carriers like united and american to move evacuees from the middle east onwards. for now, though, the u.s. prioritizing getting american citizens out. several thousand have left the country already, the pentagon says. a senior state department official says there are still several thousand more. the pentagon acknowledging helicopters have left the airport not once, but twice to pick up evacuees.