San Juan — A 6.4-magnitude earthquake struck Puerto Rico before dawn on Tuesday and was followed three hours later by an aftershock measuring 6.0. They were the largest in a series of quakes that have struck the U.S. territory in recent days and caused heavy damage in some areas.
The mayor of the southern city of Ponce, Mayita Meléndez, tweeted that a 77-year-old man was killed. She also told WAPA television that eight people were injured. Ponce is near the quake's epicenter.
Puerto Rico's power authority tweeted that one of the country's main power plants, which sits near the epicenter, had been damaged, but officials expected to restore power to the island later Tuesday.
The U.S. Geological Survey said the quake hit at 4:24 a.m. just south of the island at a shallow depth of 10 kilometers. It initially gave the magnitude as 6.6 but later adjusted it. At 7:18 a.m., the magnitude-6.0 aftershock hit the same area. People reported strong shaking and staff at a local radio station said live on air that they were leaving their building.
Víctor Huérfano, director of Puerto Rico's Seismic Network, told The Associated Press he expects aftershocks to continue "for some time."
A tsunami alert was initially issued for Puerto Rico and the U.S. Virgin Islands but was later canceled.
Puerto Rico's governor, Wanda Vasquez, told station Radioisla she was closing government offices for the day and urged citizens to remain calm and not check damage to their homes until daylight.
Albert Rodríguez, who is from the southwest town of Guánica, said the tsunami sirens went off before officials canceled the alert. He said there is widespread damage in his neighborhood. "The road is cracked in the middle and it lifted up," he said.
The mayor of Guayanilla, Nelson Torres, told NotiUno radio station that the church in the public plaza of his town collapsed.
CBS News correspondent David Beganud says he's been told of damage in Guánica and Yauco, a southwestern city, including the collapse of some homes and of Yauco's main bridge.
Agence France Press said people wrote on social media that they were shaken awake by quake's force. One woman tweeted that she'd been "wrenched from sleep" and said, "Everybody is awake & scared all over."
A 5.8-magnitude quake that struck early Monday morning collapsed five homes in the southwest coastal town of Guánica and heavily damaged dozens of others. It also caused small landslides and power outages. The quake was followed by a string of smaller temblors.
The shaker collapsed a coastal rock formation that had formed a sort of rounded window, Punta Ventana, that was a popular tourist draw in the southwest town of Guayanilla.
Residents in the south of the island have been terrified to go into their homes for fear that another quake will bring buildings down.
The flurry of quakes in Puerto Rico's southern region began the night of Dec. 28. Huérfano told the AP that shallow quakes were occurring along three faults in Puerto Rico's southwest region: Lajas Valley, Montalva Point and the Guayanilla Canyon.
He said the quakes overall come as the North American plate and the Caribbean plate squeeze Puerto Rico.
One of the largest and most damaging earthquakes to hit Puerto Rico occurred in October 1918, a magnitude 7.3 that struck near the island's northwest coast, unleashing a tsunami and killing 116 people.