A Pakistan Airlines (PIA) passenger airplane was forced to make an unscheduled landing at Istanbul's Ataturk Airport on Wednesday following a bomb threat, an airport spokesman said. The spokesman confirmed to the German Press Agency (dpa) that passengers on flight PK709 from Lahore to Manchester had disembarked safely and that a search of the plane and luggage had revealed nothing untoward. The plane was due to resume its flight to Manchester in the evening.