Another hydrogen explosion has rocked the Fukushima Daiichi nuclear power plant, this time at the third reactor unit. Initial analysis is that the containment structure remains intact.

Two more reactors at Fukushima Daini have now achieved cold shutdown with full operation of cooling systems. Engineers are working for the same at the last unit.

Attention remains focused on the Fukushima Daiichi and Daini nuclear power plants as Japan struggles to cope in the aftermath of its worst earthquake in recorded history. A dramatic explosion did not damage containment and sea water injection continues through the night.