United States authorities are reviewing airline security after a Nigerian man attempted to blow up a passenger jet on a flight from Amsterdam to Detroit on Saturday.
The review was ordered before another scare occurred on Monday morning, coincidentally involving another Nigerian on the same airline and flying between the same two cities.
The latest incident was not a threat, although cabin crew were alarmed at the passenger's behaviour.
CNN reports Northwest Airlines flight 253 requested emergency assistance on landing after reporting a disruptive passenger.
The man had gone to the bathroom repeatedly and did not respond to flight attendants' direction an hour before landing.
No explosive device was found and the plane landed safely. It was held at a remote location at Detroit Metropolitan Airport for further screening.
Wayne County executive Robert Ficano said a Nigerian man was taken into custody by the FBI.
A Detroit FBI spokesperson said the incident was "non-serious".
Same flight as earlier attempt
The incident took place on the same flight number as the one involved in the Christmas Day incident in which a Nigerian man was charged with attempting to blow up a Northwest Airlines passenger jet.
Umar Farouk Abdulmutallab, 23, travelled from Nigeria to Amsterdam and then on to Detroit with an explosive device attached to his body, US officials say.
Shortly before the flight was due to land in the US, he allegedly attempted to detonate the device beneath a blanket but he was overpowered by passengers and crew.
Mr Abdulmutallab has been charged with attempting to destroy an aircraft with a high explosive and with placing a destructive device on a plane.
He was allegedly carrying PETN, or pentaerythritol - the same material used by shoe bomber Richard Reid who tried to destroy a transatlantic flight in 2001.
US tightens security
US President Barack Obama has ordered a review of air security measures to determine how a man carrying an explosive substance had managed to board the flight.
White House spokesperson Robert Gibbs said the system of watch-lists would also be examined after it emerged Mr Abdulmutallab, the son of a prominent Nigerian banker, was listed and known to officials, the BBC reports.
US airlines especially have tightened security after the attempt, increasing screenings and body searches and, in some cases, confining passengers to their seats without pillows or blankets for the last hour of their flight.
Mr Gibbs said "air detection capabilities" would also be examined as part of the review.