Police in the Indonesian capital have fired tear gas to disperse about 500 protesters trying to storm the Jakarta office of the US mining firm Freeport.
Demonstrators used bamboo sticks to smash the ground-floor windows but police prevented them from entering Freeport's office space.
Freeport runs the largest gold mine in the world in the Highlands of the Indonesian province of Papua, where it has been criticised for dumping waste into a large river.
Hundreds of people blockaded the mine last week to try to force Freeport to let locals look through the waste deposits for lumps of valuable metals.
The ethnically Melanesian people of Papua have long complained that Freeport's community development programme doesn't give them a fair share of profits.
About 100 people rallied yesterday in the nearby town of Timika but did not disrupt mining operations.