Anti-nuclear protesters hold signs during a mass demonstration outside the National Diet building on July 29, 2012 in Tokyo, Japan. Police have imposed tight controls on the weekly protest against restarting nuclear power plants. All 54 of Japan's nuclear plants had been offline for months, in the wake of the disaster at the Fukushima Daiichi nuclear plant. Protesters wanted the government to reconsider its energy policy but the government decided to restart the Ohi nuclear plant anyway.