Tokyo:
Japanese authorities will release slightly radioactive vapor to ease pressure at nuclear reactor whose cooling system failed.
The failure occurred after a power outage caused by Friday's massive earthquake off northeastern Japan.
Japan's nuclear safety agency says pressure inside one of six boiling water reactors at the Fukushima Daiichi plant had risen to 1.5 times the level considered normal.
The agency said the radioactive element in the vapor that will be released would not affect the environment or human health.