The entire island of Puerto Rico has been plunged into darkness after a powerful 6.5-magnitude earthquake struck early Tuesday. It’s the largest in a series of quakes that have struck the U.S. territory in recent days. Víctor Huérfano, director of Puerto Rico’s Seismic Network, told the Associated Press it's unknown how much damage the quake has caused because power and communications are down across the islands. “We expect that this will be the largest quake for now... The aftershocks will continue for some time,” he said. The Electric Power Authority has reported an island-wide power outage, but no tsunami is expected. The quake comes a day after a 5.8-magnitude temblor early Monday that collapsed five homes in the southwest coastal town of Guánica.