A powerful earthquake hit Indonesia on Wednesday, causing buildings to sway strongly in the capital, and authorities issued a tsunami warning for much of the Indian Ocean region.The US Geological Survey said the quake had a preliminary magnitude of 7.9 and hit at about 6:10 p.m. (1640 IST). It was centered about 15.6 kilometers underground in the southern Sumatra area, it said.The Pacific Tsunami Warning Center issued a tsunami warning for wide areas of the region."Earthquakes of this size have the potential to generate a widespread destructive tsunami that can affect coastlines across the entire Indian Ocean Basin," it said.In Jakarta, tall buildings swayed for several minutes, and occupants rushed down the stairs to escape.
