Dallas-area drug agents and prosecutors are joining the fight to stop narcotraffickers from using drug submarines from Colombia to get cocaine into the U.S.

The U.S. Attorney’s office for Eastern District of Texas, with offices in Plano and Sherman, is just one of a handful of jurisdictions extraditing high-level traffickers from drug subs for prosecution.

Over the past two years, the Drug Enforcement Administration’s Dallas office has helped bring drug charges against 30 alleged drug crew members, and that number is rising, local officials said.

“If we hadn't intercepted these drugs, which are mainly cocaine, it would've ended up in the Dallas area because we have cases where we've seized the drugs and we've also connected those cases back to Central and South America,” said Elaine Cesare, spokeswoman for the Drug Enforcement Administration office in Dallas.

Drug submarines are typically hand built in the jungles of South America, where they are crammed with tons of cocaine and armed with desperate smugglers. They skim beneath the surface of the Carribbean Sea and Pacific Ocean to avoid detection.

“They are very important for the smuggling of Colombian cocaine up into the North American market,” said Scott Stewart, vice president of Stratfor, an Austin based think tank that studies international narcotics trafficking trends.

U.S. Coast Guard boats and helicopters are seizing an increasing number of these subs, known as semi-submersibles, on their way to Honduras, Guatemala and Mexico.

Once the drugs make it to land, smugglers secret them up through Mexico to the Texas border, typically into Laredo and other Texas land ports. From there the drugs are driven up north, often up Interstate 35 to Dallas.

From Dallas, the drugs are transported on various highways to both U.S. coasts and Chicago for further distribution, authorities say.

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