tweet from the tsa, active shooter at ffl. shelter in place. airport closed. sniper teams are put on alert. >> we have a variety of s.w.a.t. teams out and assets out clearing the entire airport. >> reporter: no other gunman is found. >> at this point it looks like he acted alone. there's no second active shooter. >> reporter: officials won't say if the suspect is targeting someone on an arriving flight or if he's cooperating. randy kaye, cnn, new york. >> joining me with more, evan perez. what can you tell us about how this happened? >> anderson, one of the most interesting things is what happens after one of these incidents is you have witness statements and, you know, you spend a lot of time, especially investigators there on the ground, spending a lot of time trying to corroborate. at this point we're told that they have not been able to corroborate this idea that there was an altercation on the plane. they still have these witness statements and report that there might have been some kind of