A 23-year-old man from Gudja was arrested yesterday after he was in found in possession of ecstasy pills before boarding a boat party in Sliema last night.
The man threw away a container with the pills when he realised police were carrying out a search.
However, he was arrested and the container was recovered.
Investigations showed the drugs were to be sold during the party, the police said.
Meanwhile, police and customs officials searched a number of boats along the Sliema Ferries and found a quantity of alcoholic beverages on which excise duty had not been paid. The drinks were seized and investigations are ongoing.