A passenger on a Las Vegas to Phoenix flight allegedly made a threat Saturday after it was forced to return to the airport because of a mechanical problem, officials said.
U.S. Airways flight 399 carrying 130 people departed about 4:30 p.m. Saturday for Phoenix, but the Airbus 320 returned shortly after takeoff, McCarran International Airport spokeswoman Candice Seeley said.
"The passenger made some sort of threat" after the plane landed, Seeley said. She didn't know specifics.
Police were called and they met the aircraft.
Transportation Safety Administration spokeswoman Jonella Culmer said the passenger made an "inappropriate comment" as the plane taxied back to the gate.
Police and the FBI told The Las Vegas Sun that they're investigating but no arrests have been made.
"It does not appear to be terrorist related at this point," FBI Special Agent Joseph Dickey told the paper.
Calls to Las Vegas police and the FBI by The Associated Press weren't returned Saturday night.
Seeley said she believed the passengers taken another flight by late Saturday.