(CNN) The Chilean Navy has been deployed after 40,000 liters of diesel were spilled into the sea near a remote island on the country's southern coast.
The oil spill occurred on Saturday off Guarello Island on the Chilean side of Patagonia, the pristine southernmost region making up the tip of both Argentina and Chile.
Chilean mining company CAP, which mines on the island, reported the incident to the navy.
The navy said several units were deployed to the area to control the spill, which had entered the waters of the South Pacific. It reported that by Sunday approximately 15,000 liters of contaminated seawater were contained. A barge and an ocean patrol boat were dispatched to the site as part of the recovery process.
The cause of the spill was not immediately clear, and the Chilean Navy has launched an investigation.
Greenpeace Chile warned that the spill could have "devastating" environmental consequences. In a statement on Monday, the organization's national director, Matías Asun, said: "It's an extremely grave situation considering the pristine nature of the waters in which this environmental emergency has occurred. It must be considered that the zone is extremely difficult to access and that it is an area of great richness of marine mammals, like whales and dolphins, which could see themselves seriously affected in their habitat given that when coming to the surface to breathe they could meet this layer of oil."
He urged the government to make all resources available and called on CAP to hand over as much information as possible on the spill.
CAP said it would collaborate in the probe. In a statement reported by Reuters, it said it had initiated "a process of permanent monitoring in the area", in addition to its standard control and mitigation measures.
Guarello Island, in the Magallanes region, has large reserves of limestone and is used by CAP as a mining base. The surrounding areas of Patagonia are home to a diverse range of ecosystems with rare flora as well as endangered species.