In September 2008, the U.S. Coast Guard seized a 59-foot submarine 370 miles SW of Guatemala. The submarine contained four crew members and 237 (!) bales of cocaine.
An anomaly? No, because less than a week alter, another 60 footer was seized.
Between the two submersibles about seven tons of coke worth nearly $200 million was seized.
These subs are built in the jungles of Guatemala and then trucked over to the coast. The subs can range over 5,000 miles.