San Juan: A magnitude 6.0 quake shook Puerto Rico on Saturday, causing further damage along the island's southern coast, where previous recent quakes have toppled homes and schools.
The US Geological Survey said the quake hit 13 kilometers south of Indios at a shallow depth of 10 kilometers.
Puerto Rico's Electric Power Authority said outages were reported across much of southern Puerto Rico and crews were assessing possible damage at power plants.
There were no immediate reports of injuries.
It was the strongest shake yet since a magnitude 6.4 quake struck before dawn on Tuesday, knocking out power across the island and leaving many without water. More than 2,000 people remain in shelters, many fearful of returning to their homes, and others unable to because of extensive damage.
Hundreds of thousands of Puerto Ricans are still without power and water, and thousands are staying in shelters and sleeping on sidewalks since Tuesday's earthquake. That temblor killed one person, injured nine others and damaged or destroyed hundreds of homes and several schools and businesses in the island's southwest region.