A near-record number of narco submarines were intercepted crossing the Atlantic and Pacific in 2024, with drug-laden vessels appearing in new areas as traffickers increasingly use this discreet shipping method to get cocaine to international markets.
Narco subs have been around for decades, primarily used to ferry cocaine from Colombia’s Pacific coast to Central America or Mexico. But recent seizure data for these hard-to-detect boats suggest that narco subs are growing in number, reach, and sophistication.
In the past year, maritime authorities nabbed a vessel carrying some 6.5 tons of cocaine near the Azores Islands in the Atlantic, discovered a deserted narco sub near Black Johnson Beach in Sierra Leone, and intercepted another in the Pacific Ocean bound for Australia, carrying more than 5 tons of cocaine.
These transoceanic journeys show that the narco sub modus operandi is now being rolled out worldwide. InSight Crime reviewed hundreds of cases of semi-submersible vessels intercepted by authorities across the world to determine what the rising use of narco submarines tells us about drug trafficking routes and criminal dynamics.
Types of Vessels
Most narco subs intercepted are not true submarines and cannot dive beneath the surface. Instead, they sit extremely low in the water, with only a small portion visible above the surface, making them difficult to detect. Authorities commonly refer to this vessel type as a Low-Profile Vessel (LPV).
A typical LPV is around 15 meters long, with a slender, elongated shape. It features a diesel or gas engine and is built primarily from wood and fiberglass, materials that are tricky to spot using radar. The cockpit and exhaust tubes stay above water, while most of the vessel remains underwater.
There are several variations, and traffickers regularly adapt their designs in response to interdiction efforts and the availability of parts or skilled labor.
For example, after law enforcement began using thermal imaging cameras to spot narco subs, some traffickers employed devices like lead shields and heat exchangers designed to obscure the subs’ heat signal. Around 2016, many traffickers switched from using inboard to outboard motors, which are easier to install and more readily available in the remote locations where most subs are built.
The vessels are also camouflaged in paint picked to match the ocean where they sail and the climatic conditions expected during the voyage. Subs traversing shallow waters in the Pacific tend to be teal, for example, while those crossing the stormy Atlantic tend to be painted in dark blue or gray hues.
LPVs can cost as little as $150,000 to build, according to the Colombian Navy’s International Center for Research and Analysis Against Maritime Drug Trafficking (Centro Internacional de Investigación y Análisis Contra el Narcotráfico Marítimo – CIMCON), although most estimates place the cost between $1 million to $2 million. They typically require three or four pilots for their voyages.
While low-profile vessels run a greater risk of interception because they operate at the surface of the ocean, they also require less skilled labor to construct and operate than a fully submersible vessel. Their low profile means they create a small silhouette, making them tricky to spot from the sea, and their hydrodynamic shape leaves little wake, making them hard to identify from the air.
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Another important type of vessel are “narco torpedoes.” These are towable underwater canisters designed to carry large amounts of drugs, typically around 5 tons. These devices are attached to ships with steel cables roughly 200 meters long and can be towed submerged at depths of up to 30 meters. The first torpedo suspected of being used for drug smuggling was discovered in 1988 by surfers in Boca Raton, Florida.
Since then, the torpedoes used by traffickers have become increasingly sophisticated. Some are equipped with ballast systems and hydroplanes to control their position underwater. And in at least one torpedo seizure in 2005, US authorities caught a vessel equipped with a radio buoy, which allows traffickers to disconnect drug shipments to evade authorities and later retrieve the cargo.
Fully Submersible Vessels (FSVs) are the most sophisticated type of narco sub, capable of diving completely underwater, often up to about 30 feet below the surface. They can transport up to 10 tons of cocaine, are invisible to radar, and are equipped with advanced GPS and navigation systems.
Building an FSV is an enormous undertaking. Construction requires expert engineering skills and large investments ranging from $2 million to $4 million, according to CIMCON. But the large costs pay dividends for the traffickers. FSVs have only been discovered on land, suggesting that once they are out to sea, they are almost impossible to detect.
The only FSV caught while actually delivering a drug shipment was seized in Venezuela in 2022. The submarine was traveling inland, along the Arauca River, suggesting that it was used to transport cocaine from Colombia to Venezuela, avoiding detection from criminal groups and authorities in an unsafe border area.
The Shipyards
Of the 240 narco sub seizures analyzed by InSight Crime, over half were built in artisanal shipyards along Colombia’s Pacific coast.
The country’s western departments are home to dense jungles and winding rivers that connect to the open sea. Tucked deep within estuaries, camouflaged by thick vegetation, and strategically positioned close to rivers and inlets, these makeshift shipyards are the epicenter of narco sub construction.
Located in mostly deserted areas, each clandestine shipyard is a small hub of criminal entrepreneurship that brings together drug suppliers, skilled craftsmen, naval engineers, seamen, and security workers, in addition to representatives of deep-pocketed criminal groups, which have the finances needed to fund the project and can wait months for a payoff once the drugs reach their final destination.
Data compiled by CIMCON shows that authorities have discovered dozens of these sites: 26 in Nariño, 10 in Cauca, and three in both Valle del Cauca and Choco between 2019 and 2023.
Nariño and Cauca are some of Colombia’s main coca cultivation hotspots, and the strong correlation between cocaine production and the presence of the artisanal shipyards is logical: cocaine must travel only short distances on land to reach these narco submarine departure points.
SEE ALSO:Colombia’s ‘King’ of Drug Subs Goes Down But Vessels Proliferate
While many artisanal shipyards are clustered on the Pacific coast, others have also been found in Brazil, Venezuela, Guyana, and Suriname in recent years, a reflection of how more and more drug traffickers are using the vessels to directly ship cocaine to lucrative European markets.
Some particularly sophisticated vessels have also been built far inland, where access to materials and skilled labor is higher. For example, in 2000, Colombian authorities discovered a half-built submarine in a warehouse in a suburb of Bogotá. The 100-foot-long vessel allegedly had a capacity of 15 tons, police estimated at the time.
The sub was likely going to be completed in Bogotá, disassembled, and transported to the Pacific coast, where it would be reassembled, police added. Authorities found Russian documents alongside the vessel, causing them to speculate on the involvement of Russian criminal groups in the submarine’s construction.
In 2019, European authorities seized a 22-meter LPV that they believe was constructed in a shipyard near the Brazilian city of Manaus. The vessel then travelled 1,200 kilometers down the Amazon River before crossing the Atlantic Ocean to reach the Spanish coast of Galicia. It was the first interdicted narco sub known to have crossed the Atlantic to Europe.
Interception Numbers Rise
Authorities seized a near-record number of narco subs in 2024, making 30 successful interdictions, according to data analyzed by InSight Crime. Most of these subs were seized while plying Pacific drug routes between South and Central America. Of the vessels in our database, 81% were discovered in Pacific waters or along the coastline.
Colombian authorities try to intercept these vessels in rivers and estuaries before they reach open water, where detection becomes much harder. Despite these efforts, only one in four narco sub seizures occurs on land or in rivers, according to the analyzed data. Once the subs are in open water, interception becomes extremely challenging, with interdiction rates as low as 5%, depending on conditions, according to US security officials.
“LPVs, due to their design and intent to evade detection, generally follow routes that exploit gaps in traditional surveillance coverage,” a spokesperson from the Joint Interagency Task Force South (JIATF), which monitors drug trafficking routes in the air and maritime domains, told InSight Crime.
The vessels are sometimes aided by a network of fishing boats and smaller vessels, which serve as refueling stations at strategic points along the routes, according to CIMCON. Although some narco subs can carry up to 1,350 gallons (5,000 liters) of fuel, they may require refueling sooner based on sea conditions or detours to avoid authorities.
In 2014, US Southern Command leader General John Kelly testified to Congress that, between limited resources and the large number of vessels encountered, only 26% of all the suspected maritime drug trafficking crafts spotted by US authorities were pursued.
“I simply sit and watch it go by,” the commander told Congress.
Like all seizures, the data collected only reflects narco sub incidents known to law enforcement, and any estimates of an actual interdiction rate or the number of subs active in the region are stabs in the dark.
The Routes
The tendency of traffickers to scuttle their subs even after successful journeys complicates the efforts of law enforcement to understand exactly where drugs come ashore. But the location of interdictions, cases of beached vessels, and court testimony offer clues.
On the Pacific side, the lengthy and relatively unpoliced coasts of Guatemala and southern Mexico have long been prized by drug trafficking organizations as a hub for maritime and air drug shipments, according to testimony from law enforcement officials.
Traffickers also appear to have turned their attention to Costa Rica, which recorded an unprecedented stint of five narco subs beached on the country’s southern coast between 2017 and 2019, an early indicator of the country’s rising prominence as a major cocaine transhipment center for criminal organizations in the region.
Similarly, in the Atlantic, narco subs appear to be destined for Central America and southern Mexico. The Honduran drug trafficking clan Montes Bobadilla received drug shipments from Colombia onboard narco subs, according to US court documents. Members of the group remain at large, and the 2024 discovery of long channels cut from the Honduran Caribbean coast to a property linked to the clan suggests that the group has continued to receive large maritime drug shipments.
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“The primary routes originate in source countries of South America and transit through international waters, where the majority of LPV traffic is interdicted,” the JIATF spokesperson told InSight Crime, who added that LPVs attempting to reach the United States remain uncommon.
Seizures of transoceanic narco subs remain rare, though they have increased in frequency. Since the first confirmed case of a narco sub traversing the Atlantic in 2019, a total of twelve vessels have been caught attempting to reach European and Australian coasts. Eight of the seizures were in 2024 and 2025.
While law enforcement frequently frames such seizures as “victories” against drug traffickers, the demonstrated tendency and willingness of criminal groups to load multi-ton loads of cocaine onto these vessels is more a signal that the method remains highly successful despite the interdictions.
Floating Coffins
Once a narco sub is spotted, authorities often attempt to stop the vessel and bring its crew into custody. Boarding suspected subs is notoriously dangerous, and most vessels are built with a plug so they can be quickly scuttled by traffickers when the drug shipment reaches its destination, destroying the record of the journey.
Traffickers also occasionally scuttle narco subs during interdiction attempts, though changes in US and Colombian law have made it a crime to be spotted onboard unflagged vessels — regardless of whether authorities seize drugs or recover the craft — with the hope of detaining more skilled narco sub crews and reducing the incentive to destroy evidence.
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Despite the changes, grizzly incidents still occur. In February 2025, an officer for the Trinidad and Tobago Coast Guard drowned while searching a narco sub at sea when traffickers removed the plug after authorities stopped the vessel.
Narco subs have also occasionally killed their crew. For example, in 2023, Colombian authorities found a “ghost vessel” traversing the Pacific with the corpses of two crew killed from the inhalation of fumes from the diesel engine.
The crew of narco submarines refer to the vessels as “coffins.”