Some of the drug found in St Paul's Bay.
Three women and a man were arrested on Thursday afternoon after a police raid on a tenement in St Paul's Bay yielded cannabis and cocaine ready for trafficking.
The police said the raid followed days of observation and involved the Drug Squad and the Special Intervention Unit.
The arrested persons are aged between 20 and 33 and live in St Paul's Bay, Mellieħa and Rabat.
A magisterial inquiry has been launched and investigations are continuing.