Peruvian authorities seized four tonens of cocaine hidden in a shipment of powdered sulfur that was due to be loaded on a ship bound for Europe, authorities said on Friday.
Interior Minister Octavio Salazar told RPP radio that several people were detained in Thursday's operation, though he withheld further information so as not to prejudice the investigation.
He only added that the drug was found inside containers belonging to the port operating company Tramarsa.
"This is very important because it allows us to unravel an organization in operation. We're making progress in nabbing gangs of drug traffickers with foreign associates," Salazar said.
Peru is second in the world only to Colombia as a producer of coca leaf and cocaine, and traffickers ship huge drug shipments by sea.
This was not the first time that Peruvian authorities have confiscated drugs in the port of Callao north of Lima - last month an organization was dismantled that was planning to send almost 400 kg (880 pounds) of drugs from Mexico hidden in a cargo of 887 wooden planks.
In September 2009 police also discovered a cargo of 4.5 tonnes of cocaine hidden in a shipment of canned artichokes being sent to Spain.