Narcosub

A narco-submarine (also called drug sub and Bigfoot submarine) is a type of custom-made ocean-going self-propelled submersible vessel built by drug traffickers to smuggle drugs. They are especially known to be used by Colombian drug cartel members to export cocaine from Colombia to Mexico, which is often then transported overland to the United States.

Newer narco-submarines are fully submersible, designed specifically to be difficult to detect visually or by radar, sonar and infrared systems.

Cargoes carried are typically several tons of cocaine. For example, in 2015 the largest cargo of 7.7 tonnes (17,000 lb) was seized on a semi-submersible which had been tracked by aircraft.

During the 1980s, go-fast boats became the drug-smuggling vessel of choice in many parts of the world. These boats can be detected by radar; as radar coverage improved, Colombian drug cartels developed less easily detected semi-submersibles from the 1990s.

In 1988, an unmanned 6.4 m (21 ft) submarine was found off Boca Raton, Florida. It was designed to be towed by a boat, and submerged by remote control. Although the sub was empty, authorities suggested that it must have been designed for smuggling contraband, since the hatch could only be opened from the outside.

The first time the U.S. Coast Guard found one containing drugs, authorities dubbed it Bigfoot because they had heard rumors that such things existed, but none had actually been seen. In late 2006 a Bigfoot was seized 145 km southwest of Costa Rica carrying several metric tonnes of cocaine. In 2006, US officials say they detected three; in 2008, they were spotting an average of ten per month, but only one out of ten was intercepted. Few were seized, as their crews scuttle them upon interception and they sink within a minute or so. By 2009, the U.S.A. detected as many as 60 narco submarine related events, and it was calculated that they were moving as much as 330 metric tonnes of cocaine per year. Costing up to two million dollars each to construct, the submarines can move enough cocaine in a single trip to generate more than 100 million USD in illicit proceeds for the traffickers.

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Wikipedia