Four men and a woman face extradition after being arrested during a series of raids connected with organised crime.
Sixteen Irish nationals were also arrested as part of Operation Wireless, which was ordered by Garda Commissioner Martin Callinan to target selected suspects.
More than 50 raids were carried out across Dublin and involved members from several units.
Gardai said four men and a woman were held on European Arrest Warrants, before being brought before the High Court.
They are wanted in other European countries, including France, Poland and Lithuania, for a variety of alleged crimes.
Other arrests were made for alleged drugs and theft offences.
A Garda spokeswoman said the force is committed to the investigation of criminal activity nationally.
"As part of this strategy we continue to target individuals involved in criminal activity," she added.
The raids involved members of the Criminal Assets Bureau, the Garda Bureau of Fraud Investigation, National Bureau of Criminal Investigation, Garda National Drug Unit and regional detective units under the co-ordination of the Assistant Commissioner, National Support Services in conjunction with the Assistant Commissioner, Dublin Metropolitan Region.