American Airlines spokesman Tim Smith said a male passenger refused to comply multiple times with directions from the flight crew.
Gann said the man and his bags were removed from the flight, and FBI agents and airport security questioned him. The FBI said agents determined there was no wrongdoing. The man was released without being charged and was allowed to take a different flight.
Smith said the aircraft was also searched before departing Salt Lake City for Dallas/Fort Worth International Airport.
Flight 1476 originally left Portland at 12:30 p.m. and was scheduled to land at DFW Airport at 4:15 p.m.