Satellite images show that the nuclear test site is “primed and ready” as tensions between North Korea and the US continue to grow.
US-based analysts 38 North say that the images show “continued activity around the North Portal, new activity in the Main Administrative Area, and a few personnel around the site’s Command Centre.
A separate report from the Voice of America says that Kim Jong-un is preparing to detonate a nuclear device “in a tunnel” on Saturday to mark the Day of the Sun – the 105th anniversary of former leader Kim Il-sung’s birth.
North Korea regularly stages shows of military force to coincide with important dates in its history.
A US National Security Council official said: “We have no comment at this time but we will be watching closely.”
Earlier this week North Korea threatened to defend itself by “powerful force of arms” after a US Navy aircraft carrier was deployed in to the Sea of Japan.
In response US President Donald Trump said he is “sending an armada” to the Korean peninsula.
A nuclear test would be the most serious development yet in the ongoing fall-out between North Korea and the west.
Satellite images show Kim Jong-un escalating nuclear action
Wed, April 12, 2017
New satellite images show in great detail how Kim Jong-un is escalating North Korea's nuclear weapons programme.
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Figure 1. Activity continues at the North Portal
Pungyye-ri has shown signs of activity
Pungyye-ri is an underground test centre
Where is the North Korea nuclear test site?
Punggye-ri is an underground facility located in mountainous terrain in North Hamgyong Province, 30 miles from Kilju City.
So far it has been used to test five nuclear devices with the first test occurring on October 3, 2006. The resulting blast had an explosive force of less than one kiltonne, leading many to think the bomb “fizzled” rather than detonated properly.
The second test, in 2009, came amid a succession crisis in the country. The 2.35 kilotonne blast was interpreted by many as a show of strength after then-leader Kim Jong-il suffered a major stroke. Following the test, the UN passed a resolution banning the country from any further nuclear testing.
Kim Jong-un is reportedly preparing to launch a nuclear weapons test on Saturday
In 2013, Pyongyang announced it had tested "a miniaturised and lighter nuclear device with greater explosive force than previously”, that created an earthquake of magnitude 5.1. It was speculated that the test involved uranium, which would have marked a significant leap forward in the North’s nuclear programme, but this was never confirmed.
In January 2016, another 5.1 magnitude earthquake was measure in Punggye-ri, which the government announced was the result of a successful hydrogen bomb test.