Hundreds of fishermen protested outside Peru's biggest oil refinery on Tuesday after an oil spill on the Peruvian coast.

The spill was caused by waves from an undersea volcano eruption in the South Pacific island of Tonga.

The men congregated in the province of Callao, near Lima's capital, outside the refinery. Authorities believe 6,000 barrels of oil leaked in the area rich in marine life, according to Peru's environment minister, Rubén Ramrez.

The fishermen carried a large Peruvian flag, fishing nets, and signs that read "no to ecological crime," "economically disadvantaged families," and "Repsol killer of marine fauna," referring to the Spain-based company that manages the La Pampilla refinery, which processes around 117,000 oil barrels per day, according to its website. They demanded to talk with corporate officials, but no one from the company had approached them.

“There is a massacre of all the hydrobiological biodiversity,” said Roberto Espinoza, leader of the local fishermen.

“In the midst of a pandemic, having the sea that feeds us, for not having a contingency plan, they have just destroyed a base of biodiversity.”

Italian ship unloads in La Pampilla

On Saturday, an Italian-flagged ship was pumping oil into La Pampilla when it was tossed around by heavy waves, causing the spill. The leak happened "because of the violence of the waves," Repsol stated in a statement on Sunday.

Waves crossed the Pacific as a result of the eruption. Two individuals perished on a beach in Peru, and minor damage was reported from New Zealand to Santa Cruz, California.

The waves coated the sand with a slick black liquid, mixed with little dead crustaceans, on Cavero beach, northwest of the facility, on Tuesday.

Guano birds, seagulls, terns, tendrils, sea lions, and dolphins are among the animals most harmed by the leak, according to Juan Carlos Riveros, a biologist and scientific director in Peru for Oceana, an organization dedicated to protecting the world's oceans.

“The spill also affects the main source of work for artisanal fishermen, since access to their traditional fishing areas is restricted or the target species become contaminated or die,” Riveros said. “In the short term, mistrust is generated about the quality, and the consumption of fishing is discouraged, with which prices fall and income is reduced.”

The spill is estimated to have contaminated 18,000 square meters of beach on Peru's Pacific coast, according to the country's environmental assessment and enforcement agency.

Repsol "has not adopted prompt actions to prevent cumulative or more significant harm that affects the soil, water, flora, wildlife, and hydrobiological resources," the Peruvian agency said in a statement.

Another local fishermen leader, José Llacuachaqui, who was monitoring the cleanup, said the workers were only collecting the oil that had made it to the beach, not the crude in the saltwater.

“That is preying, killing, all the eggs, all the marine species,” he said.