A US airliner was forced to make an emergency landing after a foul smell emanating from the within the aircraft caused breathing difficulties for a number of passengers.

JetBlue Airways flight JBU944 was en route from Long Beach Airport in California to Fort Lauderdale International Airport in Florida when it was forced to land at Will Rogers World Airport in Oklahoma City at 2.22am CDT (8.22am BST).

While the odour was originally thought to be emanating from the cockpit, KFTW, an Oklahoma City-based affiliate of CBS, has since claimed authorities have determined the smell, whose cause remains unknown, originated from the back of the aircraft.

The smell was so intense that left approximately 25 of the 135 passengers on board the Airbus A320 needing treatment for breathing problems, with five of them rushed to hospital by one of the eight ambulances that attended the scene.

Oklahoma City Fire Department confirmed the aircraft had landed safely and that ambulances deployed oxygen tanks to help struggling passengers breathe.

JetBlue flight JBU944
JetBlue Airways flight JBU944 was en route from Long Beach in California to Fort Lauderdale in Florida. KOKH FOX 25