Protests against a $5 billion gold mining project that's set to drain three lakes in northern Peru's Cajamarca region are mounting amid warnings of a repeat of last year's fatal confrontations with authorities.

The protests against the Conga mining project, led by Colorado's Newmont Mining Corp., have gone on since work on the project began in 2010 and gained momentum after President Ollanta Humala took office in July 2011. At least five protesters have died in clashes with law enforcement agents sent in by Humala, and several ministers in his cabinet have resigned over the project.

Protesters oppose mine developer Minera Yanacocha's plans to drain the lake into reservoirs it will build and use the lake sites for developing the mine. Yanacocha, majority owned by Newmont (51.35 percent), says its plan will ensure water reaches downstream residents year-round. The protesters say more than the supply of water is at stake in the planned destruction of the lakes.

Yanacocha is a joint venture between Newmont Mining, which has headquarters in Denver, Compania de Minas Buenaventura (43.65 percent) and the International Finance Corp. (5 percent). It is the largest-ever private sector investment project undertaken in Peru.

Newmont and its partners are accused of ignoring both the protesters and local authorities. The Peruvian Times has reported the company's high-handed attitude toward local authorities has played a significant role in the regional protest and fed into existing mistrust.

As the dispute flared, Humala sent in riot control agents but the confrontation backfired, resulting in deaths during protests.

The government is now seeking reconciliation with the protest groups but still wants the gold mine to go ahead. The protesters say nothing short of a cancellation of the project will end their campaign.

Humala, who came to power on a reform mandate widely welcomed by Peruvians, is facing mounting unrest that questions the government's legitimacy.

Construction on the mining project has been on hold since the protests began last year. The protesters reacted angrily to the project managers' offer to build reservoirs that would ensure regular water supplies instead of the lakes' seasonal flows.

The protesters argue emptying of the lakes to open the area for gold mining will destroy their livelihood, contaminate ground water resources and irrevocably ruin the area.

Conga is said to hold 6.5 million ounces of gold and 1.7 billion pounds of copper.

Cajamarca Regional President Gregorio Santos, one of the anti-mining activists, said residents won't allow the lakes to be turned into open-pit mines. He called the project non-viable.

Santos wants to run for president in Peru's 2016 election, La Republica newspaper reported.