Japanese officials have launched an inquiry in order to establish the cause of the radioactive leak at the Fukushima Daiichi plant. Tests showed that water in the plant’s third reactor had radiation levels that were 10,000 times higher than normal. A revision of safety measures has also been ordered after two workers were hospitalized after it was discovered they had not been wearing the proper corrective footwear and had ignored a radiation alarm. The Japanese Nuclear Safety Agency has gone no further than saying that the reactor may have been damaged, but they denied that the reactor core has cracked. The government has asked that residents within the 20-30km exclusion zone around the plant evacuate volountarily, after being advised to stay indoors.