Rescue efforts are under way in south-western Japan to help victim of a powerful earthquake that hit the region a day after an earlier deadly terror.
Some 20,000 troops are being deployed in the operation in Kyushu region after the magnitude-7.3 quake at 01:25 on Saturday (15:25 GMT Friday).
Report says at least 18 people have been killed and hundreds injured.
Dozens of people are feared trapped in the rubble of collapsed buildings. The quake on Thursday killed nine people.
Roads have been damaged and big landslides have been reported over a wide area. Some 200,000 households are now without power.
There are fears that forecast rain could set off more mudslides.
The extra troops are being sent to Kyushu to help police and fire fighters.
“We are making every effort to respond,” Chief Cabinet Secretary Yoshihide Suga said.
The second quake which was at a depth of 10km (six miles) near Kumamoto was much bigger and hit a wider area than the one that struck the city of Kumamoto on Thursday night.
Kumamoto prefectural official Tomoyuki Tanaka said the death toll was climbing by the hour.
Thousands of people spent the night on the streets and in parks where they were huddled under blankets looking dazed and afraid.
There are many reports of people trapped inside buildings, including at least 60 inside an old people’s home.
Report says village has been evacuated after a dam collapsed as a result of the quake, public broadcaster NHK says.
Japan’s nuclear authority said the Sendai nuclear plant was not damaged.
Local media reports that a small eruption occurred at Mt Aso following the tremor.
A research geophysicist with the US Geological Survey (USGS), Gavin Hayes in Colorado, said the latest earthquake would hamper the earlier rescue operation that was already under way.
He said more damage could be expected as the earthquake had been shallower and the fault-line had been much longer.
“The ground surface would have moved in the region of 4-5m (yards). So, you are talking very intense shaking over quite a large area. And that’s why we’ll probably see a significant impact from this event,” Gavin Hayes explained.
According to Japan’s seismology office, Thursday’s magnitude-6.2 quake caused shaking at some places as intense as the huge earthquake that hit the country in 2011.
The 2011 quake sparked a huge tsunami and nuclear meltdown at the Fukushima power plant.
Most of those who died in Thursday’s quake were in the town of Mashiki where an apartment building collapsed and many houses were damaged. More than 1,000 people were injured.
About 40,000 people initially fled their homes, with many of those closest to the epicentre spending the night outside, as more than 130 aftershocks had hit the area.