A magnitude 8.2 earthquake hit Indonesia, Wednesday, September 12.

The undersea quake hit at about 6:10 p.m. (7:10 a.m. EDT), the U.S. Geological Survey said. It was centered 80 miles southwest of Sumatra island at a depth of 18.6 miles.

“Earthquakes of this size have the potential to generate a widespread destructive tsunami that can affect coastlines across the entire Indian Ocean Basin,” the Pacific Tsunami Warning Center said, warning that waves could hit Indonesia and Australia within an hour, and Sri Lanka and India within three hours.