Tennis superstar Naomi Osaka has pledged to donate any prize money she wins from this week's tennis tournament to earthquake relief efforts in Haiti.

Osaka's father was born in Haiti.

The powerful magnitude 7.2 earthquake struck southwestern Haiti on Saturday, killing at least 304 people and injuring at least 1,800 others as buildings tumbled into rubble. Prime Minister Ariel Henry said he was rushing aid to areas where towns were destroyed and hospitals overwhelmed with incoming patients.

The epicenter of the quake was about 125 kilometers west of the capital of Port-au-Prince, the U.S. Geological Survey said, and widespread damage was reported in the hemisphere’s poorest nations as a tropical storm also bore down.

Haiti’s civil protection agency said on Twitter that the death toll stood at 304, most in the country’s south. Rescue workers and bystanders were able to pull many people to safety from the rubble. The agency said injured people were still being delivered to hospitals.

Henry declared a one-month state of emergency for the whole country and said he would not ask for international help until the extent of the damages was known. He said some towns were almost completely razed and the government had people in the coastal town of Les Cayes to help plan and coordinate the response.

Over the weekend, Osaka tweeted that it was hard to look at the devastation.

The Associated Press contributed to this report.
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