Three people were killed on Friday at a gold and copper mine run by PT Freeport Indonesia, a unit of U.S miner Freeport McMoRan , local police in Mimika in the Indonesian province of Papua said.
Police suspect unidentified gunmen shot dead two men near and burned another men to death inside a car, police said.
Freeport is facing a prolonged strike at its giant Grasberg mine, but it was not clear if the shooting was linked to that dispute or to a simmering independence movement in the remote region. One protester was killed earlier this week.
We confirm that there was a shooting and we're investigating it, a police spokesman in the Mimika capital of Timika said.
Two army officers and two company security risk management officers were shot and wounded when they came to investigate, police said.
We are working with the police and security personnel to address the situation, said Freeport Indonesia spokesman Ramdani Sirait told Reuters.
An eight-day strike at Grasberg in July led the company to suffer a production loss of 35 million lb (15,876 tonnes) of copper and 60,000 ounces of gold.
The current two-month strike by unionised workers, about half of Freeport's 23,000 Indonesian workers, is the longest stoppage in Indonesia's mining industry.