A tsunami warning for a wave measuring 1 metre (3.28 ft) was issued after the earthquake

Tokyo:

A powerful earthquake of magnitude 7.1 has struck Kumamoto prefecture on Japan's southern main island of Kyushu. The epicenter of the tremors was at a depth of 10 kilometers below the sea surface, the Japan Meteorological Agency (JMA) said.

Authorities have issued a tsunami warning, with waves of up to one meter (3.28 feet) expected. Residents in coastal areas have been urged to move to higher ground and follow official evacuation instructions.

Broadcaster NHK said that waves of up to that level may already have been recorded.

The Japanese government issued emergency earthquake warnings for Kumamoto, Nagasaki, Kagoshima, Fukuoka, Saga, Oita, and Miyazaki prefectures, all on Japan's southern Kyushu island.

Second Quake In A Week

A quake with a magnitude of 7.2 hit northern Japan on June 25 but caused no deaths or major damage.

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.