Following an explosion at a nuclear power plant Saturday, officials confirmed that radioactive leakage from the plant, which began before the explosion, was receding and that there were no signs of a major meltdown. Tens of thousands of people were forced to evacuate the surrounding areas of two nuclear plants near the quake's strike zone, which has hindered efforts to find survivors. While safety officials said the leak of radioactive materials was relatively small, they told the International Atomic Energy Agency that they would be distributing iodine to people who reside near the two nuclear plants that were damaged during the quake, in order to protect their thyroid glands from radiation exposure. Japanese media confirmed three workers at the Daiichi plant had already suffered exposure. "At this point, there has been no major change to the level of radiation leakage outside, so we'd like everyone to respond calmly," Japan's chief cabinet secretary, Yukio Edano, announced in a news conference Saturday night. Japan relies on nuclear power to generate more than one-third of the country's electricity, since the nation does not have access to substantial coal or oil resources.