PYONGYANG, NORTH KOREA — North Korea conducted its sixth and most powerful nuclear test at the underground Punggye-ri Nuclear Test Facility on Sunday. br br According to the U.S. Geological Survey, the underground explosion resulted in a 6.3 magnitude earthquake. Estimates put its explosive yield at 120 kilotons, reported 38 North. br br There is speculation this weekend's test bomb will form the warhead component of the Hwasong-14, North Korea's inter-continental ballistic missile. This ICBM can reportedly hit Alaska.