Yanacocha, one of Latin America's largest gold mines, produced 1.5 million ounces of gold in 2010, some 1.6 percent of the world's output.
The mine, partly owned by Peruvian precious metals miner Buenaventura
The latest flare-up could test leftist President Ollanta Humala, who took office in July promising to calm debilitating conflicts between rural communities and companies that have threatened to delay some 200 mining and oil projects nationwide.
The mine said protesters are trying to pressure the mine to sign a community relations pact that would give local communities 200 million soles ($72 million).
Newmont's shares were down 1 percent at $66.13 on Monday while spot gold was off slightly at $1,667 an ounce.
($1 = 2.75 soles)
(Reporting by Teresa Cespedes; editing by Jim Marshall)