The level of radiation around Japan's Fukushima No.1 nuclear power plant is high enough to affect human health, Chief Cabinet Secretary Yukio Edano said on Tuesday, NHK Television reported.
He said 400 millisieverts of radiation per hour had been detected around the plant's No.3 reactor building at 10:22 a.m. local time (01.22 GMT), four times higher than the acceptable radiation level for humans.
The No.1, No.2 and No.3 reactors are all releasing hazardous radioactive material.
All residents within a 20 kilometer radius of the Fukushima No.1 nuclear power plant have been evacuated, Japan's National Police Agency said.
The plant operator Tokyo Electric Power Co. said the problem could develop into a critical ''meltdown'' situation after part of the No. 2 reactor's container vessel was damaged following a hydrogen explosion at 6:10 a.m. (21.10, Monday GMT), Kyodo reported.
Meanwhile, temperatures have been rising slightly in Units Five and Six of Fukushima No. 1.
Radioactive iodine and cesium were detected in Tokyo following a blast at reactor No.4 on Tuesday, Jiji Press reported. Radiation levels in the city stood at 0.809 microsievert at 10 a.m. (01.00 GMT), about 20 times the level observed on Monday.
Blasts at Fukushima No. 1 in northeastern Japan have escalated concerns about a possible nuclear disaster in the country, which was devastated by a powerful 9.0-magnitude earthquake and subsequent tsunami on Friday.
Cooling systems at the Fukushima plant failed following the earthquake, resulting in blasts at Units One and Three on Monday. Unit Two also overheated on Monday, but the cooling system recovered a few hours later.
MOSCOW, March 15 (RIA Novosti)
