North Korea carried out on 3 September what it claimed was a successful underground test of a hydrogen bomb designed to be mounted on its intercontinental ballistic missiles (ICBMs).
The country’s sixth and largest nuclear test thus far was carried out “to examine and confirm the accuracy and credibility of the power control technology and internal structural design newly introduced into manufacturing [an] H-bomb” set to be carried by an ICBM, Pyongyang’s Central News Agency (KCNA) reported that same day.
The announcement was made shortly after an artificial earthquake was detected at around 12:30 h local time some 22 km east-northeast of Sungjibaegam, which is located near North Korea's known nuclear test site at Punggye-ri.
It is still unclear, however, just how powerful the blast was. While the US Geological Survey and the China Earthquake Administration both detected a magnitude 6.3 quake, the Korea Meteorological Administration (KMA) measured the quake’s magnitude at 5.7, compared ith the 5.04 it measured during the North’s fifth nuclear test.
The Ministry of National Defence (MND) in Seoul estimated the yield of the latest nuclear test at 50–60 kilotons, much stronger than that of the North’s previous nuclear test in September 2016, which was estimated at 10 kt. The US government has yet to release information about its measurements on the yield of the explosion.
The KCNA claimed that no radioactive materials leaked during the test and that there was "no adverse impact on the surrounding ecological environment", both of which, if confirmed, could deny foreign intelligence experts the possibility to gather crucial data to evaluate the test.
Want to read more? For analysis on this article and access to all our insight content, please enquire about our subscription options: ihs.com/contact