Peru’s President Ollanta Humala has declared a state of emergency in a northern region that has seen bitter protests against a gold mine project.
Mr Humala said the measure would last 60 days and allow security forces to restore public services shut by rallies and marches against the mine.
US firm Newmont halted work on the huge $4.8bn (£3.1bn) open-cast mine last week after protesters were injured.
Those against the project say it will destroy local water supplies.
Protests against the proposed mine have been escalating and have seen sabotage of machinery and clashes with the police.
“Using my constitutional powers, I introduce a state of emergency in the provinces of Cajamarca, Celendin, Hualgayoc and Contumaza,” President Humala said.
He blamed the impasse over the project on local officials.
“Every possible means has been exhausted to establish dialogue and resolve the conflict democratically, but the intransigence of local and regional leaders has been exposed – not even the most basic agreements could be reached to ensure social peace and the re-establishment of public services,” he said.
Newmont, based in Denver, Colorado, is the majority owner of the Conga project, which was to begin production in 2015 and is an extension of Yanacocha, Latin America’s biggest gold mine.
The project, located some 3,700 m (12,140 feet) above sea level, involves moving the water from four lakes high in the mountains into reservoirs the company would build.
The protesters say the reservoirs do not adequately replace the lakes, which also provide groundwater for agriculture and irrigate pasture for livestock.
Cajamarca is Peru’s leading dairy and livestock region, and activists fear that pollution from the mine could affect agriculture.
The Newmont Mining Corporation says its plans have been drawn up in consultation with local communities and meet the highest environmental standards.
It says the Conga mine will generate thousands of jobs.
Deputy Environment Minister resigned two weeks ago, saying the official environmental impact studies on the project were “weak, outdated and lacking in credibility”.