A powerful 7.0 magnitude earthquake hit southern Japan today, the US Geological Survey said, a day after another powerful tremor killed at least nine people in the same area.
The quake hit Kumamoto prefecture of the main island of Kyushu at 1:25 AM (2155 IST today) at a depth of 10 kilometres, the USGS said.
The Japan Meteorological Agency, which put the magnitude at 7.1, initially issued a tsunami warning for the western coast of Kyushu island, where hundreds were injured in a quake late yesterday, but later lifted it.
Public broadcaster NHK reported that waves of about one metre may have already reached the shore.
Several aftershocks rattled the area after today's earthquake, the Japanese Meteorological Agency said.
NHK said there were multiple reports of fresh injuries and that a bridge in Kumamoto city had collapsed, though that could not be immediately confirmed.
There were several reports of people being trapped under debris at various locations, and the broadcaster showed images of rescue workers removing debris from atop a collapsed house in an apparent search for anyone trapped underneath.
Other footage showed residents gathering in a park and also scenes from the NHK bureau in Kumamoto city immediately after the quake, with objects falling off desks and shelves.
A 6.5-magnitude quake that struck late yesterday killed nine people and injured nearly 900.
Shotaro Sakamoto, a Kumamoto prefectural official, said today's quake was of the same class in terms of the shaking felt on the ground.
"The latest earthquake felt as strong as, or stronger than the original one," Sakamoto, told AFP.
"It was really strong... Many people on the street appeared panicked."
The latest quake came as officials said they did not expect the death toll from Thursday's quake to rise.
Japanese Prime Minister Shinzo Abe is due to visit Kyushu later tomorrow.
