A magnitude 7.4 earthquake struck southern Japan early on Saturday morning, triggering a tsunami advisory.
The quake's epicentre was near the city of Kumamoto and measured at a depth of 40 km (25 miles), the U.S. Geological Survey said.
The USGS minutes earlier reported a 7.1 quake with a depth of 7 km close to the same location.
The Japan Meteorological Agency issued a tsunami advisory, which identifies the presence of a marine threat and asks people to leave coastal regions, for the Ariake and Yatsushiro seas.
Local broadcaster NHK said the advisory suggested a possible wave of one metre in height.
© Thomson Reuters 2016