Company has interrupted production at its Timbopeba mine and part of its Alegria mine after prosecutors ordered the evacuation of an area around the nearby Xingu dam.
Copper prices rebounded as investors scooped up material at lower prices after heavy losses the previous day on fears that strong US economic data could spur tighter monetary policy.
China's appetite for overseas metal seems to be fading, with Yangshan copper import premiums falling to $28.50 a tonne, the lowest since at least 2012.