On the Sea of Japan coast, about 65,000 people have left their homes, as an unprecedented series of powerful earthquakes shakes northern Japan. At least 21 people are dead and more than 1,800 have been treated at hospitals.
Rescue efforts are being hampered, because highways buckled or are buried by landslides, making it impossible for fire trucks and ambulances to reach some areas.
Rescuers from Japan's Self Defense Forces, arriving by helicopter, described the sight below as devastation of a degree they could not have imagined.
Desperate survivors scrawled "SOS" on the ground, or marked improvised landing sites for the choppers.
Tokyo Fire Department Disaster Response Chief Norio Aida says the helicopters are proving to be invaluable.
He says the helicopters are the only practical way to get the most seriously injured to hospitals.
Those in Niigata Prefecture who were lucky enough to emerge unscathed from Saturday evening's initial quakes are enduring a series of aftershocks, many a magnitude five or stronger.
The horizontal swaying and vertical pounding, of an acceleration seismologists say is unprecedented in Japan, has terrified thousands of people in the region.
Earthquake section chief Masahiro Yamamoto, at the Japan Meteorological Agency, says this is the first time on record here so many strong quakes have occurred in such a short period of time.
Yamamoto warns survivors to be very careful. He says the aftershocks worsen the danger of landslides, because the ground is already unstable from Japan's latest typhoon, which killed nearly 100 people last week.
Many hospitals are overcrowded, with the injured being treated in hallways and parking lots. Hospital administrators say medicines are in short supply.
Some towns say they are in desperate need of food, water, blankets and portable toilets.
Thousands of people are spending a second night outside, keeping warm in front of bonfires or portable oil heaters. Their homes, if not destroyed or severely damaged, have no heat, water or electricity.
Prime Minister Junichiro Koizumi says his government will do whatever it can for the region.
The prime minister says he will ask Parliament to pass budgetary measures to aid the area. Mr. Koizumi called his Cabinet into emergency session Sunday evening.