People walk past a TV screen broadcasting news of the suspected nuclear test by the Democratic People's Republic of Korea, in Seoul, South Korea, Feb. 12, 2013. The South Korean Defense Ministry believed that the Democratic People's Republic of Korea (DPRK) has conducted a nuclear test on Tuesday, a local TV station reported. The DPRK said on Tuesday that it has successfully conducted a third nuclear test to safeguard national security against U.S. hostile policy, the official KCNA news agency reported. [Xinhua]