F-15s Escort Airliner Back to Portland

Updated 8:12 p.m. EST

Two F-15 fighter jets escorted a flight bound for Hawaii back to Portland International Airport after a passenger became disruptive Wednesday afternoon.

A TSA official has confirmed to CBS News that Hawaiian Airlines flight 39 from Portland to Kahului Airport in Maui returned to Portland after a passenger made threatening remarks and refused to store his carry-on bag.

The captain made the decision to declare an emergency. The plane landed at 4:16 p.m. without incident.

Federal authorities said late Wednesday that the disruptive passenger has been released without charges. The FBI says there is no known link to terrorists.

The FBI says it questioned a 56-year-old man from Salem, Ore., and turned the matter over to federal prosecutors.

Military officials say the jets were sent up Wednesday as a precaution.

The action comes amid heightened concern about airline security and the charge that a Nigerian man tried to blow up a jetliner bound for Detroit on Christmas Day.

Keoni Wagner, vice president of public affairs with Hawaiian Airlines, told the station it was a very "low level" incident involving one passenger.

The FAA has confirmed the "level 1" incident, reports CBS affiliate KOIN in Portland. According to the FAA and the Royal Aeronatical Society, a level 1 disturbance includes the passenger receiving a verbal warning because of a disturbance. It is the lowest level of the three levels of passenger disturbance.

Portland station KATU reports that the flight with 231 people aboard left Wednesday morning, but got turned around about 90 minutes later and headed back.