Thousands of Japanese citizens within a six-mile radius of the Fukushima nuclear plant have been injured by the blast as they continue the struggle to contain radiation leaks at the crippled reactor. Thousands of people were evacuated as radiation rose to 1,000 times the safe level and pressure grew, fueling fears of an explosion. With growing tension at the plant, 150 miles north of Tokyo, a second state of emergency was declared as pressure rose in two reactors at the facility. Earlier, officials had proposed releasing radioactive vapor into the atmosphere in a bid to prevent an explosion after its cooling system had failed. The country's nuclear safety agency says pressure inside the reactor had now risen to 2.1 times the level considered normal. It's possible that radioactive material in the reactor vessel could leak outside, but the amount is expected to be small, and the wind blowing towards the sea will be considered, according to Chief Cabinet Secretary Yukio Edano: Residents are safe, after those within a 3km radius were evacuated and those within a 10km radius are staying indoors, so we want people to be calm, he added. Previously, officials had said there was no leak of deadly radiation from the crippled facility in Onahama city, about 170 miles north-east of Tokyo in the Fukushima prefecture, but they had already evacuated around 2,800 residents within a two-mile radius of the plant. Mr. Edano said the nuclear power plant developed a mechanical failure in the system which cools the reactor after it was shut down in the earthquake. He said the measure was a precaution, there was no radiation leak and the facility was not in immediate danger. Plant workers are now scrambling to restore cooling water supplies, but warned there was no prospect of an immediate success. At this time, water levels at the facility have NOT reached critical levels. Currently, there are 55 operating nuclear power plants in Japan.