Gardaí will review security checks on mail in An Post and at airports and ports following the parcel bomb attacks in London.
The review will examine the possibility of tightening up security procedures and the threat posed by devices igniting while being handled by postal, airline or ferry staff or the risk of such an ignition happening during a flight or a sailing.
Sources said the review was standard in response to a security incident and did not necessarily mean there was any fault in current systems.
Gardaí are conducting an investigation after it emerged that the three incendiary devices sent to three London transportation hubs on Tuesday appeared to have been posted in Ireland.
Sources said a security review would run in parallel with the criminal investigation into who sent the parcels.
The Garda Security and Intelligence Section at Garda HQ is involved in the review, while the Special Detective Unit is leading the criminal investigation.
“All of these issues are looked at every time there is an incident,” said one security source.
The source said that while such parcel bombs typically involved “robust movement” to ignite, such as tearing or ripping open an envelope, it “depended on how they were packaged”.
The source said: “There are transportation concerns. There is potential it could go off when it travels. But it’s very difficult to screen everything, particularly if they are well concealed or protected.”
The source said there was screening at An Post sorting offices, but said there were literally millions of packages and that suspect packages would get attention.
Another source said scanning of parcels was conducted by airline and security authorities, not An Post.
An Post told the Irish Examiner: “We are working closely with the Gardaí on this investigation. Ensuring the safety and security of our people as they transport, sort and deliver mail is our number one priority.
“An Post has procedures in place for dealing with suspect packages and an expert security team to manage such incidents, and train and advise staff and managers on an ongoing basis.”
Dublin Airport Authority said security issues around cargo on aircraft was a matter for the airlines.
Aer Lingus parent company IAG made this statement on behalf of IAG Cargo: "Robust Security measures are in place as prescribed by Department of Transport, Tourism and Sport’s National Civil Aviation Security Programme (NCASP), and not for disclosure to the general public."
When asked for a copy of the NCASP document, the Department of Transport said: "The document is not for public dissemination."
The Irish Examiner has yet to receive a response from Ryanair.
A statement from Stena Line said: “Due to strict client confidentiality agreements, Stena Line is not at liberty to discuss publicly any of its customer contract arrangements so it has no comment to make on whether it does or does not work on behalf of An Post. On the issue of security checks, Stena Line works closely with a number of statutory agencies on both sides of the Irish Sea and is fully compliant with all the associated requirements placed upon it.”
The Irish Examiner has yet to receive a response from Irish Ferries.
Foreign Affairs Minister Simon Coveney said he reacted with “dismay, anger, and embarrassment” at what he said was the “warped thinking” behind the attacks.
The Department of Justice said Minister Charlie Flanagan had been briefed and Garda authorities were in “close and continuous contact with their UK counterparts”.
Gardaí are investigating if a fourth package - received at Glasgow University, resulting in an evacuation - is linked to the three other parcels.