Four people were arrested and 18 kilos of cannabis grass were seized in an operation by the police Drugs Squad that started on Monday.
The police said the cannabis was being brought into Malta from Sicily.
The people arrested are a 37-year-old man and a 36-year-old woman from Sliema, a 32-year-old man from Gżira and a 41-year-old Englishman who lives in Msida.
Two people have already been arraigned.