A 43-year-old, a 31-year-old and one other male were arrested shortly after 10.30pm by members of the garda National Bureau of Criminal Investigation, who had travelled to Limerick from Dublin to oversee the operation.

It is understood that one of the men jumped 30 feet from an upstairs window of a house in an attempt to escape from gardai.

He sustained injuries in the fall and was being treated at the Mid-Western Regional Hospital this Tuesday morning.

The men, whose nationalities have not been revealed, were being sought after warrants for their arrest were issued throughout the EU.

A garda spokesperson could not confirm details of the warrants or where in the city that the arrests took place. "We cannot divulge details of their nationality, but it's safe to assume that in this type of operation the men would be non-Irish nationals," he said.

"With European warrants, Interpol would typically liase with national police forces in securing arrests," the spokesperson added.

Two of the men are due to appear before the High Court in Dublin on Tuesday afternoon for an extradition hearing.

The third will appear before the same court later once he has been discharged from hospital.