Japan: Nuclear crisis ‘level’ raised to Chernobyl level (7)

Japan’s Nuclear Safety Commission announced that the crisis level was being raised during a televised statement. A spokesperson for the Commission added that it was a preliminary assessment that was subject to confirmation by the International Atomic Energy Agency (IAEA).

The level seven signifies a "major accident" with "wider consequences" than the previous level, officials say.

"We have upgraded the severity level to seven as the impact of radiation leaks has been widespread from the air, vegetables, tap water and the ocean," said Minoru Oogoda of Japan's Nuclear and Industrial Safety Agency (Nisa), the government's nuclear watchdog.

One official from Tepco (the plant’s operator) said that radiation leaks had not stopped completely and could eventually exceed those at Chernobyl, Reuters news agency however reported.

Meanwhile, a nuclear safety agency spokesman told reporters the leaks were still small compared to those at the plant in Ukraine, then part of the Soviet Union. "In terms of volume of radioactive materials released, our estimate shows it is about 10% of what was released by Chernobyl," he said.

The decision to raise the threat level was made after radiation of up to 630,000 terabequerels per hour had been estimated at the stricken plant for several hours.

That would classify the crisis at level seven on the International Nuclear and Radiological Event Scale (INES).

It was not clear when that level had been reached. The level has subsequently dropped to less than one terabequerel an hour, reports said.

In comparison the Japanese government said the release from Chernobyl was 5.2 million terabecquerels.

Meanwhile a 6.0-magnitude earthquake on Tuesday prompted the plant's operator to evacuate its staff.

Tokyo Electric Power Co (Tepco) said it was checking the status of the plant after the quake, the second to hit in as many days, but said there had been no reports of problems with external power.

The aftershocks come a month after a huge quake and tsunami hit north-east Japan, leaving 13,219 people dead and 14,274 missing. More than 150,000 people have been made homeless.

The severity level of Japan's nuclear crisis had previously been set at five, the same as that of the accident at Three Mile Island in the US in 1979.

Japan has also said it is extending the evacuation zone around the crippled nuclear plant because of radiation concerns.