Third Explosion Rocks Nuclear Plant

It happened again: Japanese officials reported a third blast in four days at the crippled Fukushima Daiichi nuclear power plant, 150 miles north of Tokyo. Shortly after the explosion was heard—at about 6 a.m. Japan time—radiation levels at the site were measured to be above the legal limit. Some staff members have been evacuated, though plant management said they are “still trying to grasp” what the explosion meant. The reactor’s uranium rods, they said, were only half-covered in water, raising fears of a meltdown.