Thousands of weary survivors of Japan's deadliest earthquake in a decade prepared for a third tense night in makeshift shelters and outside as rain threatened and aftershocks raised fears of another big tremor.
A strong quake with a magnitude of 5.6 shook rural Niigata prefecture, about 250km north of Tokyo, early yesterday, two days after the first big tremor killed at least 25 people and injured more than 2,700.
The Japan Meteorological Agency said an increase in aftershocks meant there was a 40 percent chance of an earthquake of magnitude 6.0 or greater in the area in the next week.
Saturday's initial quake had a magnitude of 6.8.
Rain threatened to fall as night approached, prompting fears of more landslides and of a cold and bitter night ahead.
The Meteorological Agency warned that even relatively light rain might set off landslides and authorities in Ojiya, one of the worst-affected towns, urged more people to evacuate.
"Landslides are a worry," said a Niigata government official. "In addition, it is already very cold at night for people who are camped outside, and if it rains, this will get even worse."
Tens of thousands of people across the region have already spent two nights in evacuation centers or in the open air as the temperature fell below 10?C overnight.
Some slept in their cars with the engines running, but many petrol stations had closed after running out of supplies.
"There has been big damage to lifelines of electricity, gas and water and many people are at evacuation centers, unable to go home," Chief Cabinet Secretary Hiroyuki Hosoda said.
"The government is making every effort ... for disaster relief and reconstruction so that those affected can return to their livelihoods with peace of mind," he said.