The incident occurred on AirTran Flight 1879 from Atlanta to Orlando and resulted in the arrest of the unidentified passenger after the plane landed in Jacksonville.
A spokesman for the Jacksonville Aviation Authority said the suspect had locked himself in the lavatory and refused to come out. The pilot decided to land in Jacksonville as a precaution.
An Orlando (Fla.) Sentinel employee aboard the flight told the newspaper the suspect had apparently been drinking and, according to other witnesses, remarked "the plane was going to blow up."
The identity of the suspect was not released. Passengers who had been sitting near him during the flight were taken off the plane for questioning.
The flight was allowed to take off for Orlando early Saturday.