A rally celebrating the success of a recent nuclear test is held in Kim Il Sung square in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang on September 13, 2016.

A rally celebrating the success of a recent nuclear test is held in Kim Il Sung square in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang on September 13, 2016.
© 2016 Reuters