Three men and a woman were arrested on Tuesday in a police drug operation in St Thomas Bay, Marsascala.

The police said that a boathouse in the area had been under surveillance for a number of weeks after the police had received reports of cocaine and heroin trafficking in the area.

Drug squad officers, assisted by members of the Special Intervention Unit, arrested three men hailing from Cospicua, Qormi and Marsa at the site. They later arrested a woman in Zejtun.

Officers found a number of sachets containing brown and white powder, suspected to be heroin and cocaine.

Magistrate Caroline Farrugia Frendo is leading an inquiry.

The three men are expected to be arraigned in the coming days.