A plane carrying hundreds of passengers was forced to divert to Shannon Airport in Ireland after a written note allegedly containing a bomb threat was found on board.

Turkish Airlines flight TK-34 departed Houston, Texas just after 9pm local time on Saturday, and was due to land in Istanbul around 3.45pm Irish time.

But after discovering the note, the flight crew informed their operations centre, who in turn relayed the news to Irish authorities.

There were 227 passengers and crew on board the Boeing 777-300.

The pilot requested permission to divert from the flight path and land at Shannon airport, and was cleared to re-route.

According to the Irish Times, the airport put its emergency plan into action while the plane was still two hours away, with units from the local authority fire service dispatched as backup to the airport’s own fire and rescue service.

Ambulances from Ennis and Limerick were also called to the scene, alongside the Gardai, the police force of Ireland.

Authorities also alerted the Irish Coast Guard, and a Royal National Lifeboat Institution lifeboat was placed on standby in Kilrush until the flight crossed the west coast safely.

The flight landed safely at 11.02am and was directed to a remote taxiway where passengers disembarked safely and were taken to the terminal by bus.

The jet will remain parked until it’s scheduled flight time has elapsed. Authorities will then inspect the aircraft and speak to the crew.