this has been unfolding of course we have correspondents on the ground and now let's go over to ivor granites who is in a tokyo for us ivor so once again can you bring us the latest that you're hearing on this is a really worrying development with the new nuclear power plant in fukushima. way some hearing here is that actually out of the four walls in that plant at. daiichi has actually collapsed now. from what's believed to have been an explosion they still don't know they are still can't confirm that it was in the explosion but as you said their fear is that the plant has lost its cooling system there of course on japanese television and check japanese media here is a coolant in the system that used to cool down the reactor following it being switched off after the earthquake is the temperature there is actually over one hundred degrees centigrade which suggests that it's actually had the cooling system knocked out it's not working anymore there and from then on the fear is that it's going to melt down and that's what's believed to have caused the tension explosion still seeing white smoke