Gardaí are today questioning four people arrested yesterday in an operation investigating a suspected smuggling operation run by the "Real IRA".
A woman in her forties was arrested in north Co Louth last night as part of the ongoing intelligence-led operation involving authorities in Holland, Customs officials here, the Garda special detective unit and local gardaí.
Four men in their 30s and 40s were arrested yesterday evening and were held in in Drogheda and Dundalk Garda stations under Section 30 of the Offences Against the State Act. One man was later released without charge.
The woman was arrested during follow-up searches last night in which financial documents and cash were also seized. She is being questioned in Ashbourne Garda station in Co Meath.
During the swoop, gardaí discovered a large consignment of cigarettes in a warehouse in the Inniskeen area of Co Monaghan during searches yesterday evening. The haul is believed to be worth millions of euros.
It emerged last night that a warehouse was discovered in Holland last weekend, also containing a large consignment of cigarettes. Two men from Dundalk, Co Louth are being questioned by Dutch police on revenue offences connected with smuggling.
The operation is investigating both the financial and operational activities of the "Real IRA", a Garda statement said
A Garda spokesman told ireland.com that questioning of the suspects was getting under way today. The warehouse in Co Monaghan has been sealed off and will be examined by Garda technical officers later.
