Millions of Japanese were without drinking water or electricity Sunday, surviving on instant noodles and rice balls, two days after a powerful earthquake and tsunami hammered the northeastern coast, killing at least 1,000 people.

Although the government doubled the number of soldiers deployed in the aid effort to 100,000, it seemed overwhelmed by what’s turning out to be a triple disaster. Friday’s quake and tsunami damaged two nuclear reactors at a power plant on the coast, and at least one of them appeared to be going through a partial meltdown, raising fears of a radiation leak.

“First I was worried about the quake, now I’m worried about radiation. I live near the plants, so I came here to find out if I’m OK. I tested negative, but I don’t know what to do next,” said Kenji Koshiba, a construction worker, at an emergency centre in Koriyama.

According to officials, at least 1,000 people were killed – including 200 bodies found Sunday along the coast – and 678 were missing in the earthquake and the ensuing tsunami that hit with breathtaking force and speed, sweeping away everything in its path.

The US Geological Survey calculated the quake to have a magnitude of 8.9, while Japanese officials raised their estimate on Sunday to 9.0.

Either way it is the strongest quake ever recorded in Japan.

Teams searched for the missing along hundreds of kilometres of the Japanese coast, and thousands of hungry survivors huddled in darkened emergency centres that were cut off from rescuers and aid. At least 1.4 million households had gone without water since the quake struck and some 2.5 million households were without electricity.

Large areas of the countryside were surrounded by water and unreachable. Fuel stations were closed and people were running out of petrol for their cars.

Public broadcaster NHK said around 380,000 people have been evacuated to emergency shelters, many of them without power.

In Iwaki town, residents were leaving due to concerns they over dwindling food and fuel supplies. The town had no electricity and all stores were closed. Local police had taken in about 90 people and given them blankets and rice balls but there was no sign of government or military aid trucks.

In the small town of Tagajo, near the hard-hit port city of Sendai, dazed residents roamed streets cluttered with smashed cars, broken homes and twisted metal.

Residents said the water surged in and quickly rose higher than the first floor of buildings. At Sengen General Hospital the staff worked feverishly to haul bedridden patients up the stairs one at a time. With the halls now dark, those that can leave have gone to the local community centre.

“There is still no water or power, and we’ve got some very sick people in here,” said hospital official Ikuro Matsumoto.

One older neighbourhood sits on low ground near a canal. The tsunami came in from the canal side and blasted through the frail wooden houses, coating the interiors with a thick layer of mud and spilling their contents out into the street on the other side.

“It’s been two days, and all I’ve been given so far is a piece of bread and a rice ball,” says Masashi Imai, 56.