Meltdown Caused Nuke Plant Explosion: Safety Body

The Nuclear and Industrial Safety Agency (NISA) said Saturday afternoon the explosion at the Fukushima No. 1 nuclear plant could only have been caused by a meltdown of the reactor core.

Cesium and iodine, by-products of nuclear fission, were detected around the plant, which would make the explosion the worst accident in the roughly 50-year history of Japanese nuclear power generation. Nikkei.