Japan steps up nuclear crisis rating to Chernobyl level

Japanese officials have increased the severity rating at the Fukushima power plant to seven, the maximum level, only previously seen after Ukraine's Chernobyl nuclear accident in 1986.

The decision by the country's nuclear regulator on Tuesday (12 April) came after radiation levels of 10,000 terabequerels per hour had been estimated for several hours, posing a greater risk for human health and the environment. Radiation levels are then reported to have dropped back.

Japan had ea...