Haitians scrambled overnight to try to find survivors trapped in the rubble of collapsed buildings after a major earthquake killed more than 1,200 people and injured 5,700 in the Caribbean country Saturday.
The 7.2-magnitude quake injured hundreds more and flattened churches, homes and government buildings.
The temblor, which was felt in Cuba and Jamaica and was followed by a string of aftershocks, hit around 5 miles from the town of Petit-Trou-de-Nippes, just over 90 miles west of the capital, Port-au-Prince, at a depth of about 6 miles, the U.S. Geological Survey said.
Video posted to social media showed residents pulling stunned survivors out of the rubble of collapsed buildings after homes, hospitals, schools, churches and other buildings were damaged or destroyed.
The earthquake was a terrifying reminder of the devastating temblor that rocked Haiti, the poorest country in the Americas, 11 years ago, killing tens of thousands of people.
For Lydie Jean-Baptiste, 62, memories of the trauma have come flooding back.
"The neighbors, I saw them running and running. I said, 'What's wrong?' They said, 'Earthquake!' and I rushed to the front door," Jean-Baptiste told Reuters. "I felt really, really scared."
For a long time afterward, she said, she slept outside.
Yvon Pierre, the former mayor of Saint Louis du Sud, said he would sleep outside because of the aftershocks.
"I am strong, but this affected me psychologically, and that is probably the same as the rest of the population," Pierre said.
As well as the aftermath of the most recent quake, Haiti must also brace for the likely impact of Tropical Storm Grace, which appears to be headed toward it and could bring heavy rains and strong wind this week.
The quake also hit at a time of deep political turmoil, just weeks after President Jovenel Moïse was assassinated on July 7.
Looking to offer words of comfort to a devastated population, Prime Minister Ariel Henry said: "We need to show a lot of solidarity with the emergency."
Henry, who found himself at the helm of the struggling country after Moïse's assassination, has said officials will look to hold elections for a new president as soon as possible.
President Joe Biden said in a statement that he was "saddened by the devastating earthquake that occurred in Saint-Louis du Sud, Haiti" and pledged a U.S. response.
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"Through USAID, we are supporting efforts to assess the damage and assist efforts to recover and rebuild," he said, referring to the U.S. Agency for International Development.
USAID Administrator Samantha Power announced Sunday evening that a U.S. search and rescue team of 65 people had arrived in Port-au-Prince to help USAID teams that were already on the ground.
Tennis star Naomi Osaka, the No. 2 player in the world, was among those to offer support to Haitians at a difficult time.
In a tweet, she said she is set to start a tournament next week and will give "all the prize money to relief efforts for Haiti."