Gardai have been deployed to Spain as part of an investigation into an international organised crime gang based in Dublin.
Five men, aged in their 30s, 40s and 60s, were arrested on Monday and detained under section 50 of the Criminal Justice Act 2007.
The operation involved the National Drugs and Organised Crime Bureau as well as armed units.
On Wednesday, gardai also announced a sixth man – aged in his 50s – had been arrested in the Dublin region.
Gardai say their operations have been fully supported by Europol, the Guardia Civil in Spain and the Operational Network (@ON), which is funded by the EU Commission, led by the Italian anti-mafia investigation directorate (DIA).
Officers from Europol, the Guardia Civil and @ON were present and supporting gardai over the past 48 hours, a spokesperson said.
An Garda Siochana has also provided support to the Guardia Civil by deploying Garda officers to Spain.
Guardia Civil is understood to have made six arrests directly connected with the international investigation.
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