A man has been arrested after suspected cannabis with a street value of £900,000 was seized on Monday.
Police searched properties in Banbridge, Belfast and Lisburn.
The searches were part of a joint operation between the PSNI's Organised Crime Unit, Border Force and Immigration Enforcement.
Det Insp Pete Mullan said the seizure of was "significant" and demonstrated "commitment to removing dangerous drugs from our communities".
"Not only is it illegal to purchase these drugs but it fuels the local drug trade which causes irreparable damage and loss to many families and individuals whose lives it destroys," said Det Insp Mullan.
He added the PSNI will continue to investigate those "who profit from the misery and harm caused by illegal drugs".