Gardaí in Co Monaghan are questioning a man in connection with an alleged conspiracy to import €25 million of drugs into the country.
The man, with an address in Limerick, is being held in Castleblayney Garda Station under the Drug Trafficking Act, which allows for detainees to be questioned for seven days. He was arrested on Saturday.
The drugs were seized by police near the French border with Belgium last August.
Two men were charged yesterday in connection with the same incident.
Mr Michael Howard (33) from Knocktoran, Co Limerick, and Mr Morgan McGrath (31) from Breansha, Co Tipperary, each faced charges of contravening the Misuse of Drugs Act by conspiring to unlawfully import controlled drugs contrary to the Misuse of Drugs Regulations between August 1st and the 31st last.
They were remanded in custody to appear at a further sitting at Cloverhill Court in Dublin, next Tuesday.