In the US, the search of a flight from Shannon Airport - forced to land because of a phoned-in threat - has being scaled down.

The US Airways scheduled service flight departed from Shannon at 11.48 today.

FBI and police officers did not find anything on board US Airways Flight 777 and they believe the threat to be a hoax.

171 passengers and crew members were on board the flight - they were screened by police officers before the all clear was given.

A spokesperson for Shannon Airport declined to comment on specific matter but said all transatlantic flights from Shannon departed as normal following full airport security screening and us customs and border patrols checks. 

Michelle Mohr Spokeswoman, US Airways said "US Airways flight 777 from Shannon, Ireland to Philadelphia landed safely and without incident in Philadelphia at approximately 2PM.

We were aware of a possible security issue with the flight and out of an abundance of caution taxied the aircraft to a remote location, where it was met by law enforcement and emergency personnel. 171 passengers and 8 crew members have been deplaned from the Boeing 757 aircraft at the remote location safely using stairs and are being taken to the terminal by bus."