In a new report submitted to the IAEA, the Japanese government says it was unprepared for a nuclear accident on the scale of the one that occurred in March at the Fukushima nuclear plant, and that poor oversight may have contributed to the crisis, the BBC reports. Authorities have pledged to make their nuclear regulator, Nisa, independent of the industry ministry, which is responsible for promoting nuclear power. Nisa doubled its original estimate of how much radiation was leaked in the first week of the crisis, saying that 770,000 terabecquerels escaped into the atmosphere, up from its earlier statement of 370,000 terabecquerels. Three months later, the Fukushima Daiichi plant is still leaking radioactive material. The government plans a cold shutdown of the plant by January.