The flight, operated by AirTran, was diverted to Memphis at 6:30 Monday evening, where all 120 passengers aboard were forced to deplane. After being interviewed by the FBI and airport police, the rest of the passengers were allowed to re-board at 8:24 and continued on to Austin.
John Greaud, the vice president of operations at Memphis Selby County Airport Authority, said the unidentified "unruly passenger" did not appear to be drunk when he was taken from the plane.
One witness aboard the flight said four members of the military who happened to be on the plane pulled the passenger away from the emergency exit and switched seats so they could restrain him until pilots could land in Memphis.
Another passenger said the man was acting suicidal and saying he didn't want to live.
The FBI took the man away in a police car after about two hours of questioning and is determining if the man will be charged.
No one on the flight was injured, and the door was not opened during the flight, Geraud said.
"Everyone was really calm and in good spirits and understanding," said Tara Hamilton, who was on the flight with her young son. "Luckily there were military personnel on the plane and they were really accommodating. It could have been way worse but it wasn't that bad."
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