About 15 to 20 armed people invaded the mining camp on Sunday and fired at its security guards, Wu said. Peru's interior minister said several people were missing and that one was killed.
The attack may have been an act of revenge. In 2005, one protester was killed and two dozen others were tortured when townspeople mobilized to stop construction of the mine, which they said would cause pollution and hurt water supplies.
The mining development is run by Monterrico Metals of Britain, which was bought by Zijin Mining Group (2899.HK: Quote) (601899.SS: Quote) in 2007. Other Chinese miners have been investing in Peru, despite periodic conflicts over who controls natural resources.