Police in Spain have arrested two suspected members of the illegal Real IRA dissident paramilitary group.
The men are alleged to have been smuggling cigarettes
The Interior Ministry said the men were being held on suspicion of attempting to smuggle about £500,000 worth of cigarettes from Spain to Britain.
The men, one from Northern Ireland and the other from the Republic, were arrested in Malaga after two lorries were seized on an industrial estate.
A major shipment of cigarettes had just arrived at a nearby port.
Police said a large quantity of documents were also found in the warehouse.
The 32-year-old man from Dublin and a 42-year-old man from Lisburn in County Antrim are both being questioned at the police intelligence headquarters in Madrid.
The men had been arrested following a lengthy investigation by the authorities, said the Interior Ministry.
A Northern Ireland police spokesman said: "PSNI have been involved with assisting other European countries as part of our investigations into serious organised crime."
The Real IRA is an outlawed dissident republican organisation which was behind the 1998 Omagh bombing in which 29 people died.