[2][3][4] Newer semi-submersibles are "nearly-fully" submersible in order to reduce likelihood of detection by visual, radar, sonar, or infrared systems.
According to one press-release, the vessel carried 5.3 tons of cocaine; it was towed to Huatulco, Oaxaca, by a Mexican Navy patrol boat.
[17][18][19][20][21] Also in 2008, the U.S. Coast Guard captured a semi-submersible vessel in international waters about 563 km (304 nmi; 350 mi) west of Guatemala; it was carrying an even seven tons of cocaine.
[22][23] The 18 m (59 ft) steel/fiberglass vessel was detected by a U.S. Navy aircraft as part of Operation Panama Express, and was intercepted by Coast Guard Law Enforcement Detachment 402 aboard USS McInerney.
Five days later, an 18 m (59 ft) semi-submersible was seized in international waters by the USCGC Midgett about 322 km (174 nmi; 200 mi) south of Guatemala.
[8] After the November 5 2010 arrest of Harold Mauricio Poveda,[29] a key Mexican–Colombian link, enhanced interrogation revealed that the FARC (Revolutionary Armed Forces of Colombia) were behind the construction of submarines and were collaborating with the Sinaloa Cartel to fund their activities.
[5][34] In 2016, the U.S. Coast Guard seized a semi-submersible in international waters about 300 miles west of Panama, carrying about 6 tons of cocaine with a street value of about $200 million to U.S.
[37] In 2019, Spanish authorities apprehended a 20 m semi-submersible off Galicia, containing 3,000 kg of cocaine, in the first known incident of a narco-submarine crossing the Atlantic Ocean.
Amazon Prime Video has made Romero's book into both a television documentary account of the voyage and a drama serial, released in February and March 2022.
[43] The drug trafficker Laureano Oubiña affirmed the existence of a marine cemetery of narco-submarines near the Canary Islands (Spain).
[44] A 22 metres (72 ft) long semi-submersible made of vinyl carbon fiber, christened by its builders Poseidón was found sunk without cargo by the Guardia Civil in the Ria of Arousa in March 2023.
[2][27] On other seized craft however, officials found zinc bars used as sacrificial anodes, reducing corrosion on metal parts exposed to seawater.
The design and manufacturing techniques employed in their construction have improved over time: the boats have become faster, more seaworthy, and of higher cargo capacity.
As much of its structure is fiberglass and it travels just under the surface, the vessel is nearly impossible to detect via sonar or radar, and very difficult to spot visually.
[citation needed] These are the typical characteristics for semi-submersibles as stated by the U.S. Joint Interagency Task Force South:[48] Narco-submarines were considered by officials to be an oddity until 2000, when Colombian Anti-Narcotics Police discovered what was reported to be a half-built 36 m-long[50] true submarine in a warehouse outside Bogotá.
[50] On 3 July 2010 the Ecuadorian authorities seized a fully functional, completely submersible diesel-electric submarine in the jungles bordering Ecuador and Colombia.
[55] In August 2005, authorities discovered an uncrewed semi-submersible in the Pacific Ocean,[56] a "torpedo-style cargo container" (instead of a full-featured self-propelled ship).
The buoy designers claim a near 100% shipment delivery success, and state the "torpedo" development is evolving into remote-control using encrypted signals transmitted via satellite.
[59] Homeland Security estimate submarines carry one-third of smuggled maritime goods to United States customers, while claiming they "are clueless" about the rest.
[16] The penalty is a prison term of up to twenty years in the U.S.[65][66] The U.S. law does not apply to flagged vessels (i.e., registered with some officially recognized government).