Police have made a series of arrests on drugs charges in the Nelson region, after tip-off led to a raid at a business address in Richmond.
After the raid last Thursday, a 62-year-old man was arrested and charged with possession for supply of non-approved psychoactive substances and possession for supply of morphine.
That led to the arrest of two other people police believe were distributing the drugs on his behalf and they have also been charged with possession.
In a separate search, a 54-year-old Tapawera man was charged with cultivation and possession of cannabis for supply after the police found a sophisticated indoor and outdoor cannabis growing operation.
Detective Sergeant Chris Roberts said it showed how seriously drug-related offences are being taken.