More than 500 earthquakes of magnitude 2 or higher have occurred in and around Puerto Rico since a magnitude 4.7 earthquake struck in late December, including a 6.4 magnitude quake that caused widespread damage and power outages across the island last week. The agency warned Sunday that even more aftershocks could hit.
Over the weekend, a 5.9 magnitude aftershock rocked Puerto Rico, stunning the island in the aftermath of the 6.4 magnitude tremor.
