Workers battling to prevent nuclear meltdown at the stricken Fukushima Daiichi plant were temporarily evacuated on Wednesday morning after radiation levels became too dangerous for them to remain.
The withdrawal hampered efforts to secure safety at the atomic power plant and avert a major radiation leak. Staff returned to the plant after about an hour once radiation levels fell.
Its operator, Tokyo Electric Power (Tepco) said it was considering using helicopters to spray the crippled No 4 reactor with water and boric acid – a fire retardant – in an attempt to prevent more radiation leaks.
The 50 or so engineers, working around the clock in harsh conditions, spent Wednesday morning trying to put out a fire at one reactor and to cool others at risk of overheating and reaching criticality.