Spanish National Police (Policía Nacional), working with Spain’s Tax Agency and other partners, say they have dismantled a drug-smuggling network that used teams of strong swimmers to place cocaine into maritime containers carried on Europe-bound merchant ships a method investigators describe as the “monkey” (or “climber”) technique. Authorities announced 30 arrests and the seizure of 2 475 kg of cocaine after a 15 month investigation that began with an 88 kg discovery in a vehicle in Mijas (Málaga province) in October 2024, according to an official joint statement by Spain’s Tax Agency.
Investigators allege the network linked at least three groups including a Balkan-linked organisationcoordinating shipments originating in Colombia and moving through Spain as a gateway to other European markets. Police say loads were temporarily stored in towns and villages along the Gulf of Cádiz before being moved by road across Europe, as reported by the Guardian (15 January 2026).
How the “monkey” method worked at sea
Spanish police describe the scheme as a two-stage maritime operation. First, swimmers approached vessels while underway and helped conceal cocaine inside containers carried on board. Second, other members of the organisation travelled to Spain to retrieve the drugs by intercepting the ships before arrival including attempts near the Strait of Gibraltar or by using a “drop-off” method in which bundles are thrown overboard for recovery by fast craft.
Authorities cite several incidents illustrating the model. In one case in mid-2025, a ship bound for Cádiz reported stowaways on deck; the alert led to the discovery of more than a tonne of cocaine hidden in a container, while the suspected recovery team escaped. In a separate episode in Portuguese waters, a ship reported armed stowaways; police say the men nonetheless managed to recover and offload drug bundles before evading authorities. Later in 2025, police arrested five men including Colombian nationals and Spain-based members of the Balkan-linked group after they allegedly used speedboats to collect narcotics, with investigators alleging coercion of crews and the use of military-style tactics.
Arrests, seizures and the wider maritime context
Alongside the cocaine, police reported seizing assault weapons, boarding ladders, nautical equipment, eight high-end vehicles, more than €166 000 in cash, and watches and jewellery valued at about €100 000. The case underscores how containerised trade and coastal approaches around southern Spain remain attractive to transnational trafficking groups, particularly when retrieval operations can be staged at sea or near approaches to major ports.
The arrests also come amid record-level maritime interdictions by Spanish authorities. On 12 January 2026, Spanish police announced what they described as their largest-ever cocaine seizure at sea: 9 994 kg found concealed in a cargo of salt on a merchant vessel intercepted in the Atlantic off the Canary Islands, an operation reported by Reuters (12 January 2026). While the two cases are distinct, Spanish investigators and international partners have repeatedly highlighted the scale and sophistication of maritime supply chains used to push South American cocaine into Europe.
Authorities have not disclosed all operational details, including the identities of ships involved in each incident, but they say the investigation remains focused on dismantling the logistics and violence-enabled recovery teams that allow container shipments to be exploited at sea.
