Drug Submarines: A Growing Threat in Europe

Portugal’s drug enforcement chief, Artur Vaz, mentioned on Monday that Latin American drug cartels are increasingly using inexpensive “drug submarines” to ferry significant amounts of cocaine to Europe. These makeshift vessels are proving difficult for coastal patrols to spot.

“Europe is literally flooded with cocaine,” Vaz stated. He added that criminal organizations are acquiring drugs in Latin America and selling them in Europe for substantial profits.

Vaz noted that while some of these cartels still utilize traditional methods—like loading drugs onto cargo ships and using high-speed boats—these submarines represent a new and pressing challenge. Contrary to traditional submarines, these are rudimentary boats designed to keep most of their hull submerged. They only show a small portion above water, painted to blend in with the Atlantic’s waves.

In early November, a drug submarine was intercepted, assisted by agencies from the UK and the US, which led to the seizure of over 1.7 tonnes of cocaine intended for the Iberian Peninsula.

The crew, consisting of two Ecuadorians, a Colombian, and a Venezuelan, claimed they were collaborating with a multinational cartel. Unfortunately for them, the poorly constructed vessel sank in the Atlantic after law enforcement took control of it.

Portuguese drug enforcement officer Vitor Ananias described the harsh conditions endured at sea: “Between the heat, the ship’s smoke, and the high waves, even one day is tough. By the end of the 15th or 20th [day], we just want to be out,” he remarked.

The successful interception seemed to rest on a tip-off about the submarine’s approach. Sheld Top, Director of the Maritime Narcotics Analysis and Operations Center (MAOC-N), highlighted the rarity of successfully intercepting such semi-submersibles and commended the Portuguese navy for their work.

Earlier in March, another drug submarine was seized, carrying 6.5 tonnes of cocaine. However, experts believe many such submarines evade capture, successfully delivering cocaine to Europe’s shores.

Interestingly, Colombian cartels first developed these submarines back in the 1980s for short trips across the Caribbean. The trend of transatlantic drug submarines, however, has emerged as cartels broaden their reach into Europe—especially as access to the U.S. market tightens.

The first submarine was seized in 2019, following a lengthy journey from Brazil to the Iberian Peninsula. The experience was characterized by anti-narcotics police as a “nightmare” for those on board.

Conditions inside these submarines are notoriously cramped, with narrow windows, limited supplies, and high-powered engines posing risks of suffocation due to exhaust fumes.

In an incident earlier this year, the Colombian Navy discovered another drug submarine in the Pacific. Tragically, two crew members lost their lives—suspected to have died from inhaling toxic gases from the engine—and two others were found in poor health, with about three tonnes of cocaine aboard.

Brazil played a pioneering role in the construction of these vessels. Journalist Javier Romero noted that as production ramps up across Latin America, the number of submarines reaching the Atlantic is likely to increase significantly in the coming years.

Romero described the submarine industry as exploitative, where crews, often taking perilous journeys in “propeller-driven coffins,” receive meager pay—sometimes less than $5,000—for their dangerous work.

“Imagine spending hours or even days locked inside one of these things. It’s just crazy,” he commented.

A new generation of drug submarines has emerged, equipped with advanced technology, such as depth sonar and anti-radar systems. These vessels offer improved designs that help minimize their radar signatures, greatly surpassing the original submarines crafted by Colombian cartels.

In July 2025, Colombian authorities seized a remotely operated narco-submarine equipped with a Starlink antenna. Although it was unladen, analysts speculate it might have been a prototype for a drone-like vessel capable of transporting up to 1.5 tonnes of cocaine while eliminating the risk of crew capture.

“Removing the crew takes away the possibility of the operator cooperating with law enforcement,” observed Henry Schuldiner, a U.S.-based investigator.