A government-appointed panel investigating Japan's nuclear disaster says the operator of the crippled plant continues to drag its feet in investigations and has tried to understate the true amount of damage at the complex. A report by the panel released Monday also says a culture of complacency about nuclear safety and poor crisis management worsened the disaster. Three reactors at the Fukushima Dai-ichi plant melted down following last year's massive earthquake and tsunami. The report faults the government and its main nuclear regulator, the Nuclear Industrial and Safety Agency, for promoting nuclear power as an entirely safe form of energy without being open about its inherent risks. The 450-page report by the 10-member panel of independent experts wraps up a series of investigations into the worst atomic accident since Chernobyl.