Traffic at Italy's second-busiest airport was temporarily suspended as investigators checked what turned out to be an apparent false alarm, and police reported no arrests after screening the passengers.
Two fighter jets scrambled to intercept the flight from Miami after Italian authorities were alerted about the possible presence of a terrorist suspect on board Alitalia flight AZ637, the Ansa news agency reported.
It said the pilot of the airliner reported no difficulties aboard the plane, which made a routine landing monitored by its air force escort.
Passengers were allowed off the plane only after questioning by police who entered the aircraft. Baggage from the flight also underwent extra security checks.