The security guard who called cops on T.I. felt threatened and frantically called 911 as T.I. walked back to his guard shack.
TMZ's obtained the 911 call ... where you can hear the guard telling the operator, "A resident is walking back here at the guard shack where I'm at."
The guard continued describing the scene, "I've been threatened by a resident and he's here now knocking on the door."
You can hear T.I. in the background telling him to step outside the guard shack because he wants his name. The guard refused to give him that information. T.I. also reminded the man he owns a home there and pays for his services.
T.I. got heated and repeatedly said, "You're making it worse for yourself, man" and warned that at some point "you're gonna have to deal with me." He does calm down and asks the guard to step outside to talk.
TMZ also obtained police video back at the station after T.I. was arrested for public drunkenness, simple assault and disorderly conduct. An officer told him he was "acting a fool" for going back to the guard shack. As you'd imagine ... T.I. strongly disagreed.