Two contractors working for US company Freeport-McMoRan were found dead near the giant gold-and-copper mine in Indonesia's Papua region.
The mine has been hit by a strike and violence for months.
Agence France news agency reports that ten people, all Indonesians, have now been killed around the mine in ambushes and in a clash with police since a strike that began in September at the company's Grasberg mine.
Ramdani Sirait, a spokesman for the company's local subsidiary, Freeport Indonesia says the latest victims, who were found dead in a vehicle owned by the US company, had apparently been shot.
He says the company received a report of an incident involving a light vehicle which fatally injured two contractors, and initial reports indicate that the vehicle appears to have been fired upon.