A Lufthansa plane. (File photo)Rajiv Gandhi International Airport, Hyderabad (File photo)A Lufthansa plane. (File photo)Rajiv Gandhi International Airport, Hyderabad (File photo)A Lufthansa plane. (File photo)NEW DELHI: The Hyderabad-bound Lufthansa aircraft which made a mid-air U-turn for Germany's Frankfurt was forced to return due to a bomb threat to the flight, a Hyderabad airport official said on Monday."The flight returned to its origin (Germany) because of a bomb threat which was received while the aircraft was still outside Indian airspace," the official told news agency ANI.Earlier, a Lufthansa spokesperson said the flight did not receive permission to land at Hyderabad's Rajiv Gandhi International Airport, and therefore returned to its source, Frankfurt, Germany's busiest international airport.Lufthansa flight LH752 departed Frankfurt at around 14.14 local time Sunday and was scheduled to land at Hyderabad early Sunday. (Developing story. Check again for details)