The arrests yesterday and revelations of a very sophisticated scam involving illegal immigration to this country, particularly through Dublin Airport, were truly shocking and exposed a significant lapse in national security at key entry points into the State. This has wide-ranging ramifications in terms of future security policy and our capacity to withstand many types of violation of our security system. This is a wake-up call given the ease with which people could enter the country with the connivance of people working at the airport, either with carriers or in any other capacity. It seems an extraordinary gap in our system that could facilitate such illegal activity organised by global crime gangs targeting Dublin and Ireland generally as an easy route.

As the Garda Síochána has indicated, while evidence has not emerged yet it may not just be people being smuggled in this manner or by other routes. There could be firearms, drugs or large sums of cash coming in through similar systems to bypass controls. Tom Clonan, a well respected security analyst, made the point that Ireland through no fault of the Garda would be Europe's weakest link. He is quoted as saying in response to this revelation that we do not know who is here.

Are we wide open for terrorists? I know that is a different paradigm from smuggling people but if they can bypass us so easily on that front it seems we need to review our national security to make sure we rid ourselves of any complacency in the system about terrorists exploiting such gaps and lapses in security for their nefarious purposes. Brexit is coming down the track with potentially very significant immigration issues arising, and issues pertaining to controls. It is alleged that the British security system has notified Dublin of its concerns about weaknesses in our national security. Will the Taoiseach ensure, and is the Minister for Justice and Equality committed to, a comprehensive national security review to ensure these types of lapses in security do not occur again?

I agree with that. This appears to have been quite a sophisticated operation. Somewhere between disembarking from an aircraft and going through passport control some people were apparently diverted and exited the airport and this seems to have been going on for quite some time.

As the Deputy is aware, a Garda operation targeting illegal immigration led to the arrests of three people, including two employees of Aer Lingus, at Dublin Airport on Sunday night. As there is an ongoing criminal investigation, I cannot say too much at this time. I understand this matter is the subject of a Topical Issue matter allowed by the Ceann Comhairle later today. There will probably be an opportunity for a discussion of a greater length at that time.

We should commend the Garda on its work in this regard. The smuggling of people, by definition, crosses international boundaries. The Garda is working with other police forces. It has a close connection with Europol and Interpol on various strands of its investigations. It is worth pointing out that immigration officers in Dublin Airport process approximately 15 million passengers per annum. Approximately 3,500 passengers were refused permission to land at Dublin Airport last year, with more than 4,000 passengers being refused permission to land across all points of entry. Constant vigilance is required. Cases like this are uncovered and investigated on foot of such vigilance. Responsibility for the security of the airport itself is a matter for the airport authorities.

Significant resources are being invested to secure our borders, for example, through the increased use of technology. The sharing of data with other jurisdictions is very important. We have a particularly close operational relationship with the UK authorities in managing the security of the common travel area between Ireland and the UK, which is so important for the future. The gathering and sharing of relevant information is an important aspect of this co-operation. The immigration and security information sharing arrangements in place between Ireland and the UK are strong and are evolving constantly. That is as it should be. Ireland introduced new regulations last year to enable the UK to collect advance passenger information from Irish carriers in respect of passengers entering the UK from Ireland. The Government is committed to providing the Garda with the necessary resources to enhance its connectivity to a range of EU and other international resources. A great deal of work is going on in this regard. This includes connecting to the Schengen information system and to other EU and Europol information sharing resources that are relevant to countering the terrorist threat. A series of measures is being rolled out at EU level to build on the current framework. Aer Lingus and the Dublin Airport Authority are co-operating fully with the Garda in this investigation. When further details become available, the Government will see to it that an overall security assessment of the airports of Ireland - the regional airports and our main airports - is carried out.

I am surprised that a national security review has not been initiated already. This is a fundamental breach. We should not be waiting around on this issue. Airports across the globe are being targeted by terrorists and different operators. We cannot be complacent about it. The Taoiseach said in his reply that "the security of the airport itself is a matter for the airport authorities". He might clarify that for me because I think it needs to be looked at fundamentally in the context of national security and when it violates national policy. In Britain, MI5 and the intelligence networks are involved in protecting the integrity of the nation's security and borders. We do not know how long this went on. The Taoiseach has said that 15 million passengers are processed each year. The passengers in this case were not processed and never wanted to be processed. The whole objective of the exercise was to bypass being processed. Given the ease with which this seems to have happened, I think it is a wake-up call for our system. The Garda needs to be involved in this. The proper guardians of the State - the intelligence system within the State - need to take this over. There needs to be an overview of what is happening. There needs to be a rigorous review of security at our ports and airports. This wake-up call should be a catalyst for the Government to do that.

As the Deputy has rightly said, we do not know how long this has been going on. It has come to light because of vigilance at another airport. There has been an ongoing assessment of the situation at our airports. While the security of the airport is a matter for the airport authority, the point is that these people, in whatever number, never got as far as passport or immigration control.

It is true to say that the authorities at Dublin Airport Authority - the premier airport in the country - have vastly scaled up the assessments of passports coming through. Everybody has that check.

The Deputy asked about terrorists. In that context, this matter is assessed with the international organisations such as Interpol and Europol. There is no evidence that indicates any specific difficulty with particular people. The matter is kept under assessment on a constant basis, as should be the case. As more details emerge, there will be a full response from the Government on what is happening and on what needs to be done to secure our place and reputation internationally.