Customs officers and gardaí have seized 50 kilogrammes of herbal cannabis in Co Donegal, with an estimated value of €500,000.
In a statement, the Revenue Commissioners said the drugs were seized in Falcarragh following a joint operation involving Revenue Customs officers from Donegal and Dublin Airport, members of the Garda National Drug Unit and gardaí from Letterkenny today.
"The drugs were detected at Dublin Airport and arrived as an air courier consignment from Amsterdam. The consignment had been declared as computer parts," the statement said.
"This operation also involved liaison with HM Revenue & Customs and the PSNI and premises on both sides of the border are being searched."
Two men from Northern Ireland have been arrested in Falcarragh and are being held at Leterkenny Garda station.