SOURCE CITED:  CBS 60 MINUTES

The semi-submersible may be only semi-seaworthy, but it's the vehicle of choice for Colombian drug traffickers.

This week 60 Minutes traveled deep into the Colombian jungle to report on the government takedown of "The Super Cartel," the most powerful drug trafficking operation in the world. Over a span of seven years, the cartel smuggled at least 912 tons of cocaine from Colombia into the U.S.

Here at Overtime, we sat down with the story's producer, Howard L. Rosenberg, to ask: How exactly did they do it? His answer: Semi-submersibles. These boats are hand-crafted submarine-like vessels that skim the surface of the ocean, virtually undetectable by air or radar.

Cartel workers build these fiberglass boats in riverside factories in the jungle, fill their bellies with narcotics, and float them downriver to the ocean, where they travel 3-5 days on the open ocean.

Rosenberg, who is a former Navy journalist, managed to not only get a tour of a captured semi-sub, he also got his hands on reams of law enforcement videos showing the boats in action, as they were chased and captured by drug enforcement officers.

"The crew is usually trained to do one thing very quickly, and that is to scuttle the boat," Howard told Overtime. "They can be arrested, but what can they be charged with? They don't have any cocaine anymore-- it's at the bottom of the ocean."

In the video above, find out more about the mysterious semi-submersible and why national security officials are concerned that terrorist groups may find a more sinister use for these stealthy watercraft.

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