As rescue efforts continued and the numbers of dead and missing rose yesterday after the earthquake and tsunami that hit Japan, fears for a nuclear facility increased when an explosion rocked a power plant in the north of the ravaged country. Authorities from Minamisanriku said 7,500 people were evacuated to shelters following Friday's quake and tsunami, but they had been unable to contact the remaining 9,500. However, they said vast amounts of debris and mud made it impossible for helicopters to reach some shelters and for the tally of evacuated residents to be confirmed. _________________________ <strong>More</strong> • <a href="http://www.thenational.ae/thenationalconversation/comment/as-globe-watches-in-horror-reasons-for-hope-in-japan">As globe watches in horror, reasons for hope in Japan</a><br/>• <a href="http://www.thenational.ae/news/worldwide/asia-pacific/japans-tsunami-survivors-survey-damage">Japan's tsunami survivors survey damage</a> _________________________ The explosion at Fukushima Number 1 nuclear power station - one of two nuclear facilities in Fukushima, 240 kilometres north of Tokyo - is believed to have destroyed the plant's walls and roof, although officials said the container surrounding the reactor was undamaged. Several staff were injured in the accident, which occurred after temperatures inside the complex had risen dramatically. Japan's nuclear safety agency rated the incident at "4" on the international scale from 0 to 7, an official said. On the International Nuclear Event Scale, a level 4 incident means a nuclear reactor accident "with local consequences". The 1979 Three Mile Island accident in the US was rated at 5, while the 1986 Chernobyl disaster was a 7. At one stage before the explosion, radiation levels reached 1,000 times normal levels in the control room and radioactive material was detected outside the plant. However, Yukio Edano, Japan's chief cabinet secretary, said radiation levels fell after the blast. "We have confirmed that the walls of this building were what exploded, and it was not the reactor's container that exploded," Mr Edano said. "We have decided to douse the [reactor] container with seawater in order to reduce risks as quickly as possible." There were reports that metal tubes containing uranium fuel could have melted. A medical team from the National Institute of Radiological Sciences, which specialises in dealing with radiation incidents, was sent to the plant. Temperatures at the plant had increased to dangerous levels because the plant's power supply and backup generators, essential for pumping water to cool the reactor, were knocked out by the earthquake. Radioactive steam was released from the plant to relieve pressure, although officials insisted this posed little risk. Overall, the estimated death toll from the disaster rose to about 1,300 yesterday after huge waves had destroyed seaside towns and villages. However, with 9,500 unaccounted for from the port town of Minamisanriku, and with reports of four trains carrying an unknown number of commuters also missing, any accurate assessment of the loss of human life is still a long way from accurate. In Minamisanriku, officials were still looking for more than half the population after the town was largely destroyed when a 10-metre tsunami slammed into the north-east of Honshu Island following the 8.9-magnitude earthquake offshore. More than 2,000km of coastline were hit, and tsunami waves travelled up to 10km inland. As much of the nation counted its dead and missing, containing the situation at the Fukushima reactor was of the highest urgency for the government. More than 50,000 residents were evacuated from the area and the authorities said they would distribute iodine, which can counteract the effects of radiation, to local people. "Everyone wants to get out of the town. But the roads are terrible," Reiko Takagi, a middle-aged woman standing outside a taxi company, told the Associated Press. "It is too dangerous to go anywhere. But we are afraid that winds may change and bring radiation towards us." The evacuation zone was expanded from 10km to 20km yesterday and those living around the plant were told to stay indoors, turn off air conditioning and not drink tap water. Washed-out roads also hampered rescue efforts. Reports said up to 400 bodies had been recovered from the coastal town of Rikuzentakata, in addition to as many as 300 earlier that were said to have been found in Sendai. Close to 600 more are confirmed as missing. In total, more than 215,000 people are staying in 1,350 shelters after fleeing their homes, thousands of which were destroyed by the flood surge. With much of the water from the tsunami having flowed back into the sea, the shocking trail of devastation near the coast was apparent yesterday. Images of wrecked towns and villages were compared to scenes from disaster movies. Houses were flattened or washed away, stacks of shipping containers were toppled and left strewn like piles of twigs and vast stretches of land were laid waste. The Japanese prime minister, Naoto Kan, surveyed the damage by helicopter. "What used to be residential areas were mostly swept away in many coastal areas and fires are still blazing there," he said afterwards. Mr Kan said at least 50,000 troops were being deployed in affected regions and nearly 200 military aircraft and 25 ships had been sent to aid recovery work. With 1.4 million people left without water supplies, residents queued to fill up buckets from drinking tanks in the streets. Electricity companies admitted it would take time to restore power to the millions whose supplies had been cut off. "All the shops are closed, this is one of the few still open. I came to buy and stock up on diapers, drinking water and food," Kunio Iwatsuki, 68, a resident queuing outside a damaged supermarket in Mito city, told Reuters. The US offered to send half a dozen ships to the area to assist rescue operations, while South Korea, China, Germany, Australia and New Zealand were among the countries to activate search-and-rescue teams and sniffer dogs. The UAE has said it has a search and rescue team on standby. Many of the rescue teams had only recently finished helping find survivors at last month's earthquake in Christchurch, New Zealand, which killed more than 150. While the death toll from Friday's earthquake and tsunami is the worst Japan has suffered from seismic activity for at least 16 years, it could have been higher were it not for early-warning systems and regulations that ensure buildings are earthquake-proof. Retaining walls and dykes are also constructed to help prevent landslides and the spread of flood water, although vast areas were nevertheless destroyed by the tsunami. Japan has an average of 1,500 tremors a year, but the last time the death toll from an earthquake ran into the thousands was in 1995, when Kobe suffered severe damage and 6,400 were killed. In some other East and South-east Asian nations earthquakes have been followed by anger that corruption had allowed the construction of fragile buildings that collapsed easily.