The army helicopters of Japan tried in vain to spread water on the Tsunami-crippled Fukushima nuclear power plant on Wednesday.

The air-borne rescue teams returned to their bases without doing any thing as higher radiation levels could not allow them to hover in the airspace around the damaged nuclear plant where four explosions took place in four of its reactors sending up and spreading radiation everywhere.

Reports said the inner shells of the reactors were ripped apart sending up radiation steam and forcing staff to leave the place. But, efforts to cool down the nuclear reactors from land were in their final stages, Chief Cabinet Secretary Yukio Edano told journalists in Tokyo .