The operator of Japan's damaged Fukushima Dai-ichi nuclear power plant is building a huge tent to cover one of the worst-hit reactors.
Officials hope the cover will keep leaked radioactive materials from spreading, prevent rainwater seepage and offer a barrier from further leaks.
The tent is being erected to provide a temporary replacement for the No 1 reactor's outer housing shell, which was destroyed in an explosion caused by high pressure the day after Japan's deadly earthquake and tsunami on March 11.
A spokesman for the power utility Koji Watanabe said Friday that construction began this week.
