The Japan Meteorological Agency lifted a tsunami alert that had been issued after a major earthquake hit the country's southwest on Tuesday.
The alert was removed on the agency's website just under two hours after the 7.1-magnitude quake, which Prime Minister Sanae Takaichi said caused several injuries, collapsed buildings and started fires.
Earlier, the agency had issued the tsunami alert after the earthquake struck southwestern Japan.
The tremor at 4:27 pm (0727 GMT) on the island of Kyushu also measured at the highest possible level seven on Japan's own Shindo scale of shaking, the agency said.
The tsunami could measure up to one metre and arrive at around 5:00 pm (0800 GMT), it said.
Broadcaster NHK said that waves of up to that level may already have been recorded.
Meanwhile, the Nuclear Regulation Authority said that no immediate abnormalities were reported at nuclear power plants after the earthquake.
Local utility firm Kyushu Electric Power said that three nuclear power reactors operating in the region when the quake struck were continuing their normal operations.
A quake with a magnitude of 7.2 hit northern Japan on June 25 but caused no deaths or major damage.
A special advisory warning
Japan is one of the world's most seismically active countries, sitting on top of four major tectonic plates along the western edge of the Pacific "Ring of Fire".
The archipelago, home to around 125 million people, typically experiences hundreds of jolts every year and accounts for about 18 percent of the world's earthquakes.
The vast majority are mild, although the damage they cause varies according to their location and the depth below the Earth's surface at which they strike.
It is haunted by the memory of a massive 9.0-magnitude undersea quake in 2011, which triggered a tsunami that killed or left missing around 18,500 people and wrecked the Fukushima nuclear plant.
On April 20 this year, a tremor measuring 7.7 hit the country's north, injuring at least 10 people and shaking large buildings in Tokyo.
This prompted authorities to issue a special advisory warning of an increased risk of earthquakes of magnitude 8.0 or stronger.
The advisory was lifted after a week.
