A major 7.8-magnitude quake hit Indonesia's northern Sumatra early Wednesday, US seismologists said, triggering a local tsunami watch. The quake struck at a depth of 46 kilometres (29 miles), just off northern Sumatra, at 5:15 am (2215 GMT Tuesday), according to the US Geological Survey (USGS).
The Pacific Tsunami Warning Center issued a watch for local tsunamis but said a widespread destructive tsunami was not expected.
Indonesia sits on the Pacific "Ring of Fire," where the meeting of continental plates causes high volcanic and seismic activity.