SANTIAGO, Chile (AP) -- A magnitude-6.5 earthquake struck off the coast of Chile on Monday, the U.S. Geological Survey said, but Chilean officials said it was not felt on land and discarded the possibility that it might unleash a tsunami.

The quake was recorded at 5:49 a.m. local time (EDT; 0949 GMT) Monday, at a shallow depth of 10 kilometers (6.2 miles), some 600 kilometers (370 miles) from the city of Puerto Quellon.

Chile's oceanographic service said it was not felt on land and discounted the possibility of a tsunami. U.S. seismologists originally estimated the magnitude at 6.8 later recalculated downward.

Chile is one of the world's most earthquake-prone countries. A magnitude-8.8 quake and the tsunami it unleashed in 2010 killed more than 500 people and destroyed 220,000 homes. It was so strong it changed time, shortening the Earth's day slightly by changing the planet's rotation.

The strongest earthquake ever recorded also happened in Chile, a magnitude-9.5 in 1960.