A tremor with magnitude-5.3 hit just southwest of the island in the afternoon, the U.S. Geological Survey said, revising its power down from an initial measurement of 5.5. It came just a few hours after a magnitude-4.9 shake hit in the same region, causing small landslides and collapsing an abandoned home weakened by the earlier quakes.
Víctor Huérfano, director of Puerto Rico’s Seismic Network, said both tremors were aftershocks related to a magnitude-6.4 earthquake in early January that caused at least one death and did millions of dollars in damage. He said an even stronger quake could still occur.
“This is unpredictable,” Huérfano said. “The tectonic plates are settling.”
Ángel Vázquez, who oversees the emergency management agency in the city of Ponce, said the house that collapsed was in the town of Lajas. The structure was empty and slated for demolition, said Kiara Hernández, spokeswoman for Puerto Rico’s Department of Public Security.
The U.S. Geological Survey said the morning quake struck five kilometers (three miles) southeast of La Parguera, at a depth of six kilometers (3.7 miles). The afternoon tremor's epicenter was 9.5 kilometers (5.9 miles) south-southeast of La Parguera, at a depth of 3 kilometers (1.8 miles).
After the first tremor, Guánica Mayor Santos Seda said there were a couple of small landslides but no one was in danger. He said crews were inspecting buildings that have been weakened by the recent series of quakes.
He said the shaking caused panic once again in his town and beyond.
“It revives the fear of many people,” he said, adding that there are still three families living in makeshift, temporary structures because they are too scared to return home.