After four people were killed amid anti-mining protests, Peruvian President Ollanta Humala declared a 30-day state of emergency in the Apurímac region on Tuesday.

Suspending civil liberties and authorizing military patrols, the government announced that extra troops would be sent to Apurímac "to restore internal peace."

The four protesters were shot dead during confrontations with the police. Aside from the deaths, 14 protesters were injured in demonstrations against a $7.4 billion copper mine project.

According to The Wall Street Journal, Humala called for calm in the region, saying, “I think that it is important to protect the lives of people, but also public goods and private property.”

As the BBC reports, the locals in the region are concerned that the copper mine project will cause environmental damage to the Andean area.

The declared state of emergency will allow police to search homes regardless of warrants and suspends the rights of Peruvians to freely assemble.

This marks the second time in 2015 that the Peruvian government has declared a state of emergency in order to counter anti-mining demonstrations. Back in May, a state of emergency was declared for 60 days in the province of Islay in Arequipa, after protests against the Tia Maria copper mine resulted in four deaths.

As reported in Reuters, Prime Minister Pedro Cateriano addressed the measures that would be taken by the state on national TV, saying, "The national police with the backing of the armed forces will take charge of keeping public order."

The recent protests, which resulted in eight police officers being injured, began on Friday and escalated on Monday.

According to The Wall Street Journal, Interior Minister José Luís Pérez Guadalupe has insisted that the protesters will not interfere with the mining project, saying, “They aren’t going to prevent the mine from going forward under any circumstances.”

“They can’t block a project of this dimension, which is an immense investment, the biggest in the past few years,” he added.