In the last nine months, 26 Albanian nationals have been intercepted at Ringaskiddy Port in Cork after attempting to enter the country unlawfully.
The figures have been released by the Department of Justice after the issue was raised in the Dáil by Fianna Fáil TD Michael McGrath.
The Cork South Central TD said these revelations indicate a pattern and the matter must now be raised by the Irish Government with the Spanish authorities.
He said there are "lapses" on the Spanish side and this is the type of issue that will come into sharp focus in the weeks ahead in the context of Brexit.
Those seeking to enter the State arrived in Cork on the twice weekly ferry service that operates from there to Santander in northern Spain.
Senior garda management travelled to Spain recently to meet with port officials there and the Guardia Civil in an effort to address the issue.
Last Monday alone, eight people from Albania were found hiding between pallets in a container on a truck that had disembarked from the ferry in Cork.
Minister for Justice Charlie Flanagan has now confirmed all 26 people found at the port since last May were refused leave to land by Immigration Officers.
Seventeen were removed from the State in accordance with Section 5 of the Immigration Act 2003 and returned to the port of their departure.
Five people sought International Protection and will have their claims dealt with in accordance with the International Protection Act 2015.
A further four people are scheduled to be returned in accordance with Section 5 of the Immigration Act 2003.
The Minister has said that all vehicles and trailers at the port are subject to checks.
The Department of Justice said that it will make a further detailed statement on the matter this afternoon.