The 20 handguns discovered by Customs officers in Dublin port shortly after the IRA ceasefire last month are believed by the security forces to have been bound for the splinter republican group, the Irish National Liberation Army (INLA), in the North.
The Luger pistols, together with 20 magazines and 200 rounds of ammunition - enough for only 10 rounds per weapon - were found in a container which was on its way to a depot in Newry.
Customs officers had kept the container under surveillance after they received information which linked it to a Dublin criminal and drug dealer living in Amsterdam.
This man, in his 40s, was previously a member of the INLA and before that had links with the Official IRA. He is reputed to have committed three murders in Dublin while building up a drugs-trafficking operation in the north of the city from the late 1970s to the mid-1980s.
He also shot and seriously injured a member of the Official republican movement in Dublin in the early 1980s.
In recent years, he has been based almost permanently in Amsterdam and is believed to have close links with another former Dublin INLA man who is also very heavily involved in drug trafficking. These two appear to have links to the Dublin gang that was responsible for shooting the journalist, Veronica Guerin, last year.
While it is not believed that this man is any longer an active member of the INLA, gardai believe contact remains between him and the organisation. In the past, members of the INLA have been arrested with arms in the Netherlands and there was evidence to suggest their arms dealing was with drugs-related criminals there.
The INLA is known to have been recruiting new members in Belfast, mostly young men in their late teens or early 20s. This is causing concern about its intentions.
The organisation has also refused to call a ceasefire and is critical of the Provisional IRA's decision to call a cessation of its campaign.
The INLA has a history of carrying out highly provocative sectarian attacks which have resulted in retaliatory violence by loyalists. The loyalist gun attack on the Loughinisland public house in Co Down in June 1994, in which six men died, was in retaliation for the INLA's killing of three loyalists on the Shankill Road in Belfast.