Peruvian customs officials seized in February 175 kilograms of gold (worth US$6 million) that is believed to have come from illegal mining.
The custom officials found evidence of money laundering from illegal mining as the exporters involved failed to prove the legal origin, possession and purchase of the 175 kilos of gold.
The three export companies whose cargo was seized are Holding Minero del Perú, C.G. Koenig S.A. and Mining & Energy Solution S.A.C.
The 175 kilograms of gold, which were about to be sent out of the country, were taken into custody from a storage container in El Callao.
Last December, the customs agency made the country's largest ever seizure of gold produced by illegal mining operations in the southeastern Amazon jungle as six mineral export companies were caught trying to send 508 kilograms of illegally mined gold out of the country. The gold was on its way to refineries in the U.S. and Italy.
Peru is the world's sixth biggest gold exporter, producing around 140 million grams of gold last year.
The South American country is cracking down on illegally mined gold and expects overall exports of the precious metal to decline by 25% in 2014 due to the measures.