A total of three flights have been redirected to Shannon Airport after alleged air rage incidents.
A number of people are in custody.
Two people were arrested following the first alleged air rage incident on board a transatlantic jet this afternoon.
Martinair flight 621 was forced to divert to Shannon where it landed safely at 3.40pm.
There were 233 passengers on board the aircraft which was en route from Amsterdam to Cuba.
Gardaí were waiting at Shannon when the plane landed and two people, a man and a woman, believed to be from Ukraine were arrested on suspicion of public order offences.
They are being held at Shannon Garda Station and are expected to be brought before a district court sitting tomorrow morning on public order offences.
That flight was cleared for take-off before 6pm this evening to continue its flight to Cuba.
The second alleged air rage incident occurred on a Delta Airlines flight from Istanbul to JFK.
The flight was diverted to Shannon where it landed at around 6.30pm this evening.
Gardaí arrested a man who is believed to be an Iranian national.
The 197 passengers from that flight will be staying overnight in local hotels.
In the third flight diversion, a Thomas Cook flight from Manchester to Toronto was two hours into its flight across the Atlantic this evening when cabin crew became concerned about the actions of a passenger.
There was no specific incident but the captain decided for security reasons to divert to Shannon.
Arrangements were being made to find a replacement crew to resume the flight.
Gardaí interviewed the man and are satisfied he did not pose a threat.