A confiscation of cocaine aboard a small fishing boat named Yorleny II is turning out to be one of the biggest at-sea drug busts this year as police continue to find hidden drugs.

U.S. and Costa Rican Coast Guard authorities intercepted the boat Wednesday night 250 nautical miles off the coast of the northwestern Guanacaste province near the Nicaraguan border. The seven-member crew was transferring packets of the drugs to a Mexican boat. Upon seeing authorities approach, they began throwing their cargo overboard.

Drug Control Police first estimated there to be about 800 kilograms of cocaine aboard, but they have since found a total of 4.5 metric tons of the drug hidden aboard the boat, on the ocean floor and on the Mexican boat, the Jurel IV.

The seizure is the biggest made by a joint effort between U.S. and Costa Rican Coast Guard authorities so far this year, according to a statement from the Public Security Ministry.

Police arrested six Costa Ricans aboard the ship identified by the last names Espinoza, 27; Gómez, 36; Mora, 27; González, 38; Espinoza, 36; and Cambronero, 47; as well as a Nicaraguan identified as Novoa, 45.

They face drug trafficking charges before the Prosecutor's Office of the Pacific port of Puntarenas, and a court yesterday sentenced them to three months preventive prison.

Police assume the drugs were being carried from the Colombian port of Buenaventura, suggesting a link between Colombian, Mexican and Costa Rican drug-trafficking operations.

-Tico Times