A routine traffic stop in Nevada more than a year ago has led to charges against three Calgary men allegedly at the centre of a multimillion-dollar smuggling and trafficking operation.

The Jan. 15 arrests are the result of a joint investigation between Alberta law enforcement teams and the United States Drug Enforcement Administration.

Charges against the trio include conspiracy to import cocaine, conspiracy to traffic cocaine, possession, trafficking and possession of proceeds of crime.

Officials say the investigation began in Nevada in October 2012 when a traffic stop found 45 kilograms of cocaine packaged in vacuum-sealed bundles in a hidden compartment beneath a pickup truck.

Investigators believe the suspects are behind the drug-trafficking operation.

The three are believed to be a major cocaine distributor in southern Alberta and are alleged to have routinely used couriers to import cocaine from the southern U.S.