The 2003 "American Idol" runner-up was on the Saturday morning Continental Airlines flight for a evening show, and concertgoers said afterward that Aiken joked on-stage about being beaten up by a girl earlier in the day.
FBI Special Agent Gary Johnson told the Tulsa World there was a dispute between a male passenger and a woman on the flight. He said the man was a former "American Idol" contestant but did not give his name.
Johnson said the dispute was over the male passenger's foot resting on the woman's armrest. He said there was an allegation the woman gave the male passenger a "minor shove" during the argument.
Tulsa Airport Authority spokeswoman Alexis Higgins said the passengers were held until FBI agents arrived to interview them.
No injuries were reported and the disturbance did not interfere with the flight of the aircraft, Johnson said. The U.S. Attorney's Office declined to file charges, he said.
Telephone calls and e-mails from The Associated Press to Aiken's publicist and manager in Los Angeles were not returned Sunday.