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A major earthquake struck southern Haiti on Tuesday, knocking down buildings and inflicting a catastrophe on the impoverished Caribbean nation, its ambassador to the United States said.

“The only thing I can do now is pray and hope for the best,” the ambassador, Raymond Joseph, told CNN.

The magnitude 7.0 quake struck about 10 miles (15 kilometers) southwest of the Haitian capital Port-au-Prince shortly before 5 p.m. Joseph said he had little information about the extent of damage from the quake, but one government official — the only one he was able to reach — told him houses had crumbled “on the right side of the street and the left side of the street.”

“He said it is a catastrophe of major proportions,” Joseph said.

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A hospital collapsed from the quake, The Associated Press reported.

Frank Williams, the Haitian director of the relief agency World Vision International, said the quake left people “pretty much screaming” all around Port-au-Prince. He said the agency’s building shook for about 35 seconds, “and portions of things on the building fell off.”