As part of a surveillance, control and patrol mission to the coast and territorial sea, with a special focus on combating international drug trafficking, the Guard's military, with the support of the Integrated Surveillance, Command and Control System (SIVICC), detected a high speed vessel, of the semi-rigid type, which was approaching the Guadiana River, showing atypical behaviour.

In view of the suspicions raised, continuous monitoring of the vessel's movements was carried out and the Maritime Team was activated to intercept it. Realising the presence of the GNR vessel, the individuals who were on board the suspicious vessel immediately fled, throwing the hashish bales overboard. In total, 48 bales of hashish were seized as well as some electronic equipment.

The Judiciary Police, the body competent to proceed with the investigation, were notified of the incident.