A powerful earthquake of 7.0 magnitude rocked Haiti just before 5 p.m. Eastern time, 10 miles southwest from the highly populated capital of Port-au-Prince, according to the United States Geological Survey, causing widespread damage and panic with the potential for a high number of casualties in the impoverished Caribbean country.

There were two aftershocks — of 5.5 and 5.9 magnitude — that followed in the last hour, and more were expected, according to David Wald, a seismologist with the survey.

“The main issue here will probably be shaking,” Mr. Wald said, “and this is an area that is particularly vulnerable in terms of construction practice, and with a highly population density. There could be a high number of casualties.”

The city has about 2 million people, according to National Geographic.

According to several news reports, a large hospital in the capital had collapsed, and people were screaming in streets full of rubble.

[...]

Since 2008, the island has been struck by at least three severe hurricanes — Gustav, Hanna and Ike — that have wrought nearly a billion dollars worth of damage and killed 800 people. All of this has taken place against the backdrop of food riots, health crises and near constant government instability and upheavals.

Raymond Joseph, Haiti’s ambassador to the United States, said in an interview on CNN that he had little information about the extent of damage but said the suffering inflicted on the was likely to be “catastrophic.”