Another powerful earthquake - measuring 6.1 on the Richter scale - hit northern Japan today and a disaster that has now claimed 31 lives continued to spread terror.
People screamed in evacuation centres as the third most powerful tremor in a series of shocks to shake rural Niigata prefecture over the past five days swayed buildings in a radius of over 200 kilometres.
Since the first quake at the weekend, almost 450 aftershocks have now occurred, 35 of them perceptible this morning. Their frequency is decreasing but the authorities are still not ruling out another major tremor.
Although today's quake brought no immediate report of casualties, more than 2,000 people had been injured previously and over 100,000 evacuees are living in crowded emergency shelters, or camped out in vehicles, afraid to go home until an all-clear from the authorities on the structural safety of buildings.
A Japanese Red Cross doctor on the scene today warned that shock and stress could see the death toll climb further. Strokes and heart failure have cost 14 lives already and the threat to the elderly is greatest.
"Many people in these shelters are old and frail," Dr Toshiharu Makishima warned. "Stress and exhaustion simply exacerbate their condition."
The initial earthquake on Saturday night measured 6.8 on the Richter scale. With Ojiya city as its epicentre, it flattened houses, precipitated landslides, tore open roads, brought down overpasses and rocked buildings as far away as Tokyo, 260 kilometres to the southeast.
A Shinkansen bullet train heading from the capital to Niigata was derailed although miraculously none of the passengers were injured.
Aftershocks have continued ever since. Coming within days of the country's worst typhoon in a quarter of a century, this has been the most deadly seismic disaster since 1995 when the city of Kobe was devastated.
The region has suffered widespread power and gas cuts, as well as disruption to the water supply as mains were torn open. The injured have overwhelmed some hospitals, and casualties have been treated in makeshift wards in corridors.
The full extent of the disaster has been emerging gradually. Some communities have been cut off by landslides or damage that has left roads impassable, and military helicopters have had to assist relief efforts.
A warning on Monday from Japan's Meteorological Agency of the possibility of more tremors above six on the Richter scale occurring within a few days has bothered people huddling in emergency shelters. "Some people feel going home is like playing Russian roulette. Some feel safer in the open," a source in Ojiya said.
But with temperatures plummeting that has brought other consequences. "It's getting very cold now," said Naoki Kokawa, relief division director of the Japanese Red Cross. "Nights can be close to zero. Keeping people warm, particularly children and elderly, is a priority, along with the provision of food, water and sufficient sanitation. The longer this goes on the greater the challenges."
The Japanese Red Cross was still helping thousands of survivors of deadly floods and landslides unleashed by typhoon Tokage last week when it launched an earthquake operation on Saturday.
While the 750-bed Nagaoka Red Cross hospital in Niigata opened its doors for the injured, Red Cross hospital disaster response teams were deployed by Tokyo, Saitama, Toyama, Niigata, Tochigi and Gunma chapters, and by the Japanese Red Cross Medical Centre at national headquarters.
Some 19 teams of doctors, nurses, pharmacists and other specialists are running mobile health clinics at emergency shelters in schools and public buildings in Ojiya, Tokamachi and Nagaoka, and providing psychological support for the traumatized.
Meanwhile, three special disaster response units resembling mini-field hospitals are providing medical services from a schoolyard in Ojiya among other places. Close to 8,000 blankets, food, water, and hundreds of kits of hygiene items and daily necessities have been distributed in an ongoing operation.