Tensions peak as North Korea conducts powerful 'hydrogen bomb' test
Earthquakes triggered by North Korean nuclear tests have gradually increased in magnitude since Pyongyang's first test in 2006.
A missile is launched during a long and medium-range ballistic rocket launch drill in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang on August 30, 2017.(photo credit: KCNA/VIA REUTERS)ByREUTERSUpdated:
