OSAKA — As the world struggles to understand the risks of a worst-case scenario at the Fukushima No. 1 nuclear plant, Tuesday's government order for residents living within a 20-km radius of the plant to finish evacuating and those between 20 and 30 km to stay indoors heightened tensions in the northeast and Tokyo regions.
Radiation levels of 400 millisieverts — levels significantly dangerous to humans — were detected Tuesday morning near the Fukushima No. 1 nuclear power plant's No. 3 reactor. At the plant's No. 4 reactor, the level registered 100 millisieverts, while the area between the No. 2 and No. 3 reactors registered 30 millisieverts.
Abnormal levels of radiation believed to be from the failing reactors were even detected as far away as Tokyo, Chiba, Tochigi and Kanagawa Prefectures, although the government and experts said the levels' effects on humans was almost negligible for now.