A magnitude 4.8 earthquake struck southern Puerto Rico late Thursday at a shallow depth in the same region that has not stopped shaking since late December.
The quake hit near the southern town of Guayanilla at a depth of 7 miles (12 kilometres), according to the US Geological Survey. The tremor initially was reported with a preliminary magnitude of 5.1.
No immediate damage was reported, although many Puerto Ricans were jolted from their beds.
It was felt everywhere, V ctor Hu rfano, director of the island's seismic network, told The Associated Press.
He said it is one of many aftershocks that have occurred since a magnitude 6.4 earthquake struck in early January, killing one person and causing million of dollars in damage along Puerto Rico's southern coast.