Massive waves of up to four metres are pummeling the coasts of Ecuador and Peru, leaving scores of ports closed and at least one person dead on Saturday, authorities said.
Jetties and public squares were submerged in some parts of Peru, sending residents fleeing to higher ground.
The waves, according to the Peruvian navy, are being generated off the US coast by winds along the ocean's surface.
Many beaches along the central and northern stretches of the country were closed to prevent risk to human life, authorities said.
Dozens of fishing boats were damaged, while those that were spared were still unable to work in the dangerous conditions.
Thirty-one fishermen stranded in the swell were rescued Saturday afternoon by the navy, while one told local radio that around 180 more remained at sea.
"There are no more supplies, no water. Our brothers and sisters are practically adrift," the man told radio Exitosa.
In neighboring Ecuador, the National Secretariat for Risk Management said a body was recovered in the coastal city of Manta.
"The Manta Fire Department reported that, at 6:00 am, the body of a missing person was found lifeless in the Barbasquillo sector," the agency announced on social media.
Huge waves were also seen crashing into the central Chilean coast in Vina del Mar, sparking warnings from authorities.
Peru closed 91 of its 121 ports until January 1, the National Emergency Operations Centre said on its X social media account.
In Lobitos, in the north, video showed a group of people on a pier running toward the shore as huge waves slammed into the structure.
Callao, which sits adjacent to the capital Lima and is home to Peru's largest port, has closed several beaches and barred tourist and fishing boats from venturing out.
"There is a major problem," La Cruz district mayor Roberto Carrillo Zavala told AFP after surveying damage via helicopter with Peru's Minister of Defense Walter Astudillo Chavez.
"The most affected have been the fishermen," Zavala said. "We hope nothing more happens, as this would significantly impact the economy."
The waves "are being generated thousands of kilometres away from Peru, off the coast of the United States," navy Captain Enrique Varea told Canal N television.
"They are waves generated by a persistent wind on the surface of the ocean that is approaching our coasts," he said.
The phenomenon began on Christmas and will last until January 1, according to the National Emergency Operations Centre.
Ecuador's authorities said a "rough" sea was expected until December 29.

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