With the use of these craft on the rise, American officials say they fear that the trafficking networks are moving away from so-called fast boats, the high-powered fishing and leisure boats that can carry about a ton of cocaine and are easier to spot, to semi-submersible and fully submersible vessels that can surreptitiously carry many more tons of drugs, which are unloaded in shallow waters or transported to shore by small boats.

More troubling for American officials is their belief that these vessels could be used by terrorists to transport attackers or weapons, though they emphasize that no use of submersibles by militants has been detected.

Drug networks historically were organized to combine the tasks of production, transportation and distribution, and they have seen little reason to cooperate with terrorists. But these new advanced submarines are built in some cases by independent contractors who may be more willing to sell the vessels to anybody offering the right price.

Photo

“These vessels are seaworthy enough that I have no doubt in my mind that if they had enough fuel, they could easily sail into a port in the United States,” said Cmdr. Mark J. Fedor of the Coast Guard, who commands the cutter Mohawk, the 200-foot vessel whose fast boat and helicopter interdicted the submersible in the Caribbean last September.

In addition to the Coast Guard ships and aircraft patrolling the seas, the American effort includes a sophisticated command center that combines intelligence from across the United States government and from nations in the region, which are increasingly cooperating to battle cocaine trafficking.

This growing American counternarcotics effort is part of a larger shift to new missions for the nation’s security and intelligence agencies after a decade spent focused on the conflicts in Iraq and Afghanistan.

That mission to sort and analyze intelligence on drug trafficking and then coordinate the response occurs around the clock behind the walls of an interagency task force in Key West, which sent the intelligence report to Commander Fedor’s ship and coordinated its response.

Advertisement Continue reading the main story

The intelligence report, based on surveillance from a Coast Guard plane over the Caribbean and intelligence tidbits from nations in Latin America, said the submersible had left Colombia headed for Honduras.

Newsletter Sign Up Continue reading the main story Please verify you're not a robot by clicking the box. Invalid email address. Please re-enter. You must select a newsletter to subscribe to. Sign Up You will receive emails containing news content , updates and promotions from The New York Times. You may opt-out at any time. You agree to receive occasional updates and special offers for The New York Times's products and services. Thank you for subscribing. An error has occurred. Please try again later. View all New York Times newsletters.

Although the craft was 300 miles away, the Mohawk was the closest American vessel to it. So Commander Fedor immediately ordered his 100 crew members to direct the ship off Honduras to intercept the craft.

Cocaine-filled submarines and semi-submersible crafts “are the Super Bowl of counternarcotics,” Commander Fedor said. “When you hear one is moving, you say: ‘Wow. Game on.’ ”

After a day’s travel, the cutter got within a few miles of the craft and deployed the cutter’s fast boat and a helicopter.

Photo

Commander Fedor said that as they approached the submersible he was on the radio with the intelligence task force, getting up-to-the-second information on what the submersible was doing. He had similar conversations two weeks later as his ship was chasing another sophisticated submersible and had to fire on it to stop, a mission also set into motion by the intelligence fusion center in Key West.

Inside the command center, officially known as Joint Interagency Task Force-South, the Departments of Homeland Security, Justice, State and Defense are joined by intelligence agencies and liaison officers from more than a dozen nations to analyze threads of information on drug trafficking. The 600-person task force is in charge of cuing ships, aircraft and counternarcotics units on the ground for interdiction missions up and down the hemisphere.

The task force’s commander, Rear Adm. Charles D. Michel of the Coast Guard, said that drug interdictions for 2012 are already up more than 50 percent from a year ago. He attributed that to a counternarcotics coalition assembled at Key West that is trying innovative and aggressive measures to cut off drug traffickers leaving South America.

The current mission, called Operation Martillo, focuses on setting up interdiction “boxes” in two zones off the coast of South America where the drugs start their voyage, and two more just offshore of the favored transshipment points in Honduras and Guatemala, where the drugs are divided up into smaller shipments and harder to track.

Admiral Michel said that while the task force consists mostly of Americans, the end game is “getting to prosecution,” which requires working “by, with and through the local partners” in Central and South America.

Advertisement Continue reading the main story

In 2011, interdiction missions coordinated by the joint task force captured 129 tons of cocaine en route to the United States — more than five times the cocaine seized over the same period by operations in the United States, where agents and officers stopped about 24 tons of the drug.

Even so, three-quarters of potential drug shipments identified by the task force are not interdicted, simply because there are not enough ships and aircraft available for the missions. “My staff watches multi-ton loads go by,” Admiral Michel said.

Joint Interagency Task Force-South has been one of the United States government’s best-kept secrets, although it does exhibit a flair for dramatic symbolism — if you know what to look for.

Whenever the headquarters contributes intelligence to guide a mission that successfully interdicts a large cache of cocaine, a flag is raised in the yard. On the banner is a large image of a cocaine snowflake with a larger red “X” across the center.