Three men were arrested by the police in separate raids on Saturday, the police said.
A 32-year-old man from Dingli was found in possession of drugs including cocaine and ecstasy which appeared to be meant for trafficking.
A 24-year-old man was later arrested in Paceville after members of the Rapid Intervention Unit found him in possession of cocaine, mephedron and ecstasy.
The third arrest was of a 40-year-old Sicilian, who was caught importing and trafficking 4kg of cannabis. The drug was found in his car shortly after he arrived in Malta.
The police said the three will be charged in court.