A powerful earthquake struck western Indonesia on Saturday, geological agencies said, but there were no immediate reports of damage or injuries. The tremor had a preliminary magnitude of 6.2 and was centered 100 kilometers (65 miles) from Sibolga, a city on Sumatra island, the U.S. Geological Survey. It struck 35 kilometers (22 miles) beneath the earth's surface. It earlier put the magnitude at 6.1, according to AP. The Indonesian geological agency put the quake's strength at 6.3 and said it hit at a depth of 18 kilometers (11 miles). The agency did not issue a tsunami warning, said local meteorologist Ali Imron. Indonesia, the world's largest archipelago, is prone to seismic upheavals due to its location on the so-called Pacific «Ring of Fire,» an arc of volcanos and fault lines encircling the Pacific Basin. In December 2004, a massive earthquake struck off Sumatra and triggered a tsunami that killed more than 230,000 people in a dozen countries, including 160,000 people in Indonesia's westernmost province of Aceh.
