A powerful 7.9 magnitude has struck off the west coast of the Indonesian island of Sumatra, triggering a tsunami warning. Here are the latest updates
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There were no immediate reports of damage or casualties but the shallower a quake, the more likely it is to cause damage. USGS originally put the magnitude at 8.2, and then 8.1, before lowering it to 7.9.
Indonesia, badly hit by the Indian Ocean tsunami in 2004, straddles the so-called “Pacific Ring of Fire”, a highly seismically active zone where different plates on the earth's crust meet and create a large number of earthquakes and volcanoes.
Additional reporting by AP
