Scores of people are sleeping in their cars after a series of terrifying earthquakes that have killed 41 people and injured around 1,500 in southern Japan.
Search efforts resumed on Sunday morning for about half-a-dozen missing people in debris-strewn communities in a mountainous area near Mount Aso, the largest active volcano in Japan.
Prime Minister Shinzo Abe said the defence ministry is co-ordinating with the US military in Japan to add US aircraft to the search and recovery effort.
Landslides from Saturday's magnitude 7.3 earthquake have blocked roads and destroyed bridges, making it difficult to access the area east of Kumamoto, a city of 740,000 on the south-western island of Kyushu.
That came just 28 hours after a magnitude-6.5 quake hit the same area, while there has been a series of terrifying aftershocks.
Some 50 residents of Ozu who planning to sleep in their cars at a public park after the earthquakes that have seen more than 90,000 people evacuated from their homes, flattened houses and triggered major landslides.
"I don't think we can go back there. Our life is in limbo," said 62-year-old Yoshiaki Tanaka, as other evacuees served rice balls for dinner. He, his wife and his 85-year-old mother fled their home after Saturday's quake hit at 1.25am local time.
About 80,000 homes in Kumamoto prefecture still did not have electricity on Sunday, the ministry of economy, trade and industry said. Japanese media reported an estimated 400,000 households were without running water.
Kumamoto prefectural official Riho Tajima said that more than 200 houses and other buildings had been either destroyed or damaged.
Hundreds of people lined up for rations at distribution points before nightfall, bracing for the rain and strong winds that were expected. Local stores quickly ran out of stock and shuttered their doors, and people said they were worried about running out of food.
Police in Kumamoto prefecture said at least 32 people had died in Saturday's earthquake. Nine died in the quake on Thursday night.
More than half the deaths were in Mashiki, a town on the eastern border of Kumamoto city that was hit hardest by the first quake.
Japan's Kyodo news agency reported that four people were missing in Minamiaso, a more rural area farther east of Kumamoto where the landslides were triggered by the second quake.
One landslide tore open a mountainside in Minamiaso from the top to a highway below. Another hit a road above a smashed house that had fallen down a ravine. In another part of the village, houses were hanging precariously at the edge of a huge hole cut open in the earth.
Yoshihide Suga, the Japanese government's senior spokesman, said the number of troops in the area was being raised to 20,000, while additional police and firefighters were also on the way.
David Rothery, professor of planetary geosciences at The Open University in Britain, said Saturday's quake was 30 times more powerful than the one on Thursday.
"It is unusual but not unprecedented for a larger and more damaging earthquake to follow what was taken to be the main event," he said.
He said in March 2011, a magnitude-7.2 earthquake in northern Japan was followed two days later by the magnitude-9.0 quake that caused a devastating tsunami that killed more than 18,000 people.
Mount Aso, near the village of Minamiaso, erupted on Saturday for the first time in a month, sending smoke rising about 100 yards into the air, but no damage was reported. It was not clear whether there was a link between the quakes and the eruption. The 5,223ft mountain is about a 90-minute drive from the epicentre.
The second earthquake seriously damaged historic Aso Shrine, a picturesque complex near the volcano. A number of buildings with curved tiled roofs were flattened on the ground like lopsided fans. A towering gate, known as the "cherry blossom gate," collapsed.