MIAMI -- On March 29, 2012, the U.S. Coast Guard intercepted a strange-looking vessel off the Honduran Caribbean coast.
When the vessel stopped, Coast Guard personnel realized it was a makeshift semi-submersible built to carry at least 3 tons of cocaine.
Nelson Penagos Molina, a Colombian charged in connection with the semi-submersible, has pleaded guilty to the case in federal court, according to court records and his Miami lawyer Louis Casuso.
The case drew international attention because at the time semi-submersibles, also known as "narcosubmarines," were a novelty.
Penagos Molina, pleaded guilty Jan. 6 before U.S. District Judge William Dimitrouleas in a case originally filed by a federal grand jury Oct. 17, 2013.
The case also implicated at least four other Colombians, some who are believed to be still at large. Two others recently also pleaded guilty.
According to court records, the case began when investigators in Colombia linked Penagos Molina and others to a drug-trafficking organization specialized in hauling large quantities of cocaine in semi-submersibles from Colombia to Central America.
"Through an extensive Colombian wiretap investigation, and with the assistance of a cooperating source familiar with the DTO's (drug trafficking organization) activities, Colombian law enforcement authorities identified the voices of the defendants speaking during numerous lawfully intercepted telephone conversations planning cocaine shipments for the DTO," according to a document in the case file.
According to the document, Penagos, 48, played a significant role in the activities of the group, but was directly involved in the transport of cocaine.
"The role of Penagos Molina was to transport money to be used as payments for the DTO's activities, including the obtainment of materials needed to construct the self-propelled semi-submersible submarines," the document says. "Each of the SPSS constructed had a capacity to carry at least three (3) tons of cocaine."
The Coast Guard website contained additional information on the vessels.
"The typical self-propelled semi-submersible -- commonly referred to as a drug sub -- can travel up to 5,000 miles," according to the article posted May 2, 2012, on the Coast Guard Compass blog.
The semi-submersible voyage linked to Penagos Molina ended on March 29, 2012, when a U.S. government patrol plane spotted the vessel.
"After receiving permission from Honduran authorities," the court document says, "the United States Coast Guard pursued the SPSS into the territorial waters of Honduras and attempted to interdict the SPSS."
But when the semi-submersible crewmen saw the Coast Guard approaching, they scuttled the vessel in 3,000 feet of water.
"No cargo was recovered," according to the document. "However, one crew member informed law enforcement authorities that cocaine was loaded onto the SPSS prior to departing Colombia."