Japan will dramatically raise its warning about the severity of a toxic water leak at the Fukushima nuclear plant, its nuclear watchdog said on Wednesday, its most serious action since the plant was destroyed by an earthquake and tsunami in 2011.
The deepening crisis at the Fukushima plant will be upgraded from a level 1 "anomaly" to a level three "serious incident" on an international scale for radiological releases, a spokesman for Japan's Nuclear Regulation Authority (NRA) said.
That will mark the first time Japan has issued a warning on the International Nuclear Event Scale (INES) since three reactor meltdowns after the massive quake in March 2011.
Water still leaking from the plant is so contaminated that a person standing close to it for an hour would receive five times the annual recommended limit for nuclear workers in a year.
A maximum level 7 was declared at the battered plant after explosions led to a loss of power and cooling two years ago, confirming Fukushima as the worst nuclear accident since Chernobyl a quarter of a century earlier.