KAMAISHI, Japan: Workers were close to restoring power to a nuclear plant's overheating reactors as the toll of dead or missing from Japan's worst natural disaster in nearly a century passed 21,000. Amid the devastation on the northeast coast left by a massive quake and tsunami, there was an astonishing tale Sunday of survival with the discovery of an 80-year-old woman and her 16-year-old grandson alive under the rubble. “Their temperatures were quite low but they were conscious. They have been already rescued and sent to hospital,” a spokesman for the Ishinomaki police department said. They were in the kitchen when their house collapsed but the teenager was able to reach food from the refrigerator, helping them survive for nine days, broadcaster NHK quoted rescuers as saying. But with half a million tsunami survivors huddled in threadbare, chilly shelters and the threat of disaster at the Fukushima No. 1 nuclear plant stretching frayed nerves, the mood in the world's third-biggest economy remained grim. Food contaminated with radiation was found for the first time outside Japan — where milk and spinach have already been tainted by a plume from Fukushima — as Taiwan detected radioactivity in a batch of imported Japanese fava beans. Tokyo's tap water, where iodine turned up Friday, now has cesium. Rain and dust are also tainted. In all cases, the government said the radiation levels were too small to pose an immediate health risk. The Fukushima plant was struck on March 11 by the 9.0-magnitude earthquake and tsunami which, with 8,450 people confirmed killed, is Japan's deadliest natural disaster since the Great Kanto quake leveled much of Tokyo in 1923. Another 12,931 are missing, feared swept out to sea by the 10-meter tsunami or buried in the wreckage of buildings. In Miyagi prefecture on the northeast coast, where the tsunami reduced entire towns to splintered matchwood, the official death toll stood at 5,053, but the police chief warned that the number could eventually rise to 15,000. Radiation-suited crews were striving to restore electricity to the ageing Fukushima plant 250 kilometers northeast of Tokyo, after extending a high-voltage cable into the site from the national grid. Engineers were checking the cooling and other systems at reactor No. 2 late Sunday, aiming to restore the power soon, operator Tokyo Electric Power Co (TEPCO) said. Fire engines earlier aimed their water jets at the reactors and fuel rod pools dumping thousands of tonnes of seawater from the Pacific. Defense Minister Toshimi Kitazawa said the temperature in all spent fuel-rod pools at the facility had dropped below 100 degrees Celsius (212 degrees Fahrenheit) — suggesting water cooling operations were having some effect. The UN's atomic watchdog Sunday noted “some positive developments” at the plant over the past 24 hours, but warned that the crisis there remained serious.