SANTIAGO, Chile (AP) - A powerful earthquake shook southern Chile on Sunday, prompting officials to order an evacuation of coastal areas to guard against a possible tsunami.

The U.S. Geological Survey put the quake's magnitude at 7.7 and said it struck at 11:22 a.m. local time (9:22 a.m. EST; 1422 GMT) near the southern tip of Chiloe Island, about 25 miles (40 kilometers) southwest of Puerto Quello and at a depth of 20 miles (33 kilometers). The area is relatively sparsely populated.

Chile's naval oceanographic service declared a preventative tsunami alert and officials began evacuating coastal areas in the southern part of the country.

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