Protesters block the way to the Yanacocha mine in Cajamarca, Peru on November 25,.

Story highlights

The state of emergency comes after weeks of protests against a gold mining project called Conga

At least 18 people were injured in protests last week

Critics say the project would affect the area's ecosystem and would leave cattle without access to water

The mining company says an impact assessment was approved and included the input of communities

CNN  — 

Peru declared a state of emergency in parts of the country after weeks of protests against a mining project, the Andina news agency reported.

The state of emergency, which begins Monday, which will last for 60 days in four areas of Cajamarca department, according to Andina. President Ollanta Humala Tasso announced the decision, described as an attempt to re-establish peace in the area, Andina reported.

The announcement Sunday came after protests against the construction of a $4.8 billion gold mining project called Conga. The decision came as union leaders refused to stop ongoing protests, Andina reported.

Eighteen people were hurt, several by gunshots, following protests on Wednesday, the department’s director of health said.

The protests took place despite an announcement Tuesday by U.S.-based Newmont Mining Corp. that work on the project would be suspended.

Newmont, which is based in Denver, Colorado, and describes itself as one of the world’s largest oil companies, said it had suspended construction on the project “for the safety of employees and community members.”

It noted that operations there and at the nearby Yanacocha mine “have experienced intermittent work stoppages as a result of ongoing protests in the region.”

The protests began when anti-mining activists expressed concern about the possible impact of the project on the local water supply, the company said in a statement on its website. “The Conga Environmental Impact Assessment was approved in 2010 after extensive review by the Peruvian government, which included significant engagement and consultation with local communities,” it said.

Critics say the mining project would adversely affect the area’s ecosystem and would leave cattle in the zone without access to water.

CNN’s Helena DeMoura and journalist Maria Belaunde contributed to this report.