MILWAUKEE (CBS 58) -- Three Mexican nationals arrested last year after investigators found cocaine hidden on a boat off the coast of Costa Rica are being extradited to the United States, federal officials announced Tuesday, Oct. 20 at a press conference at the federal courthouse in Milwaukee.

Assistant U.S. Attorney Brad Schimel of the Eastern District of Wisconsin and Drug Enforcement Administration officials said the boat held 840 kilograms of nearly pure cocaine.

The Eastern District of Wisconsin will prosecute the three, with officials saying that the case is one of the biggest drug seizures charged in the district.

Schimel was asked why a seizure off Costa Rica is being handled in Wisconsin.

"The connection to Milwaukee came because our district DEA office in Milwaukee has been so effective in going after the assets of the cartels like the Sinaloa Cartel," Schimel said.