A nuclear security drill is held in Xinbei, southeast China's Taiwan, Sept. 5, 2012. (Xinhua/Yin Bogu)

A nuclear security drill is held in Xinbei, southeast China's Taiwan, Sept. 5, 2012. (Xinhua/Yin Bogu)

A nuclear security drill is held in Xinbei, southeast China's Taiwan, Sept. 5, 2012. (Xinhua/Yin Bogu)

A nuclear security drill is held in Xinbei, southeast China's Taiwan, Sept. 5, 2012. (Xinhua/Yin Bogu)

A nuclear security drill is held in Xinbei, southeast China's Taiwan, Sept. 5, 2012. (Xinhua/Yin Bogu)