It was part of an intelligence-led operation
Revenue officers at Dublin Airport have seized drugs with an estimated street value of almost €650,000.
It was part of an intelligence-led operation.
Officers stopped a man, aged in his 40s, who had arrived in Dublin on a flight from Malaga on Wednesday.
The British national was found to be carrying 4.5kg heroin and 0.25kg cocaine.
He was arrested and brought to Ballymun garda station, where he remains in custody.
Revenue say investigations are ongoing with a view to prosecution.