North Korea's mountain nuclear test site at risk of imploding, warns Chinese scientist

Regime risks blowing top off mountain and spreading radiation across region, leading nuclear researcher says

North Korea's mountainous nuclear test site may be at risk of collapse due to repeated seismic shocks from the blasts, a Chinese scientist has claimed.

The Punggye-ri site is believed to be the location of all the regime's five most recent bomb tests and a researcher said any further detonations could cause the entire mountain to collapse.

It could cause radiation to leak out across the region, including into China, Wang Naiyan, of the China Nuclear Society, told the South China Morning Post. The increased size of the bombs made the risk of blowing the top off the mountain more likely, he added.

The paper said geophysicists at the University of Science and Technology of China in Anhui province had pinpointed all five blasts to the Punggye-ri area.

The US ambassador for the United Nations, Nikki Haley, said North Korea's leader Kim Jong-un was "begging for war" after the latest nuclear test on Sunday, the regime's biggest yet.

North Korea's Punggye-ri nuclear test site (AFP/Getty Images)

Pyongyang claimed to have detonated a thermonuclear warhead which could be fitted onto an intercontinental ballistic missile (ICMB). Then on Tuesday morning the North was reportedly seen moving a rocket resembling an ICBM towards its west coast.

The test resulted in South Korea boosting its own military capabilities. Washington and Seoul agreed to lift restrictions on South Korean missiles, according to the South Korean presidential office, allowing Seoul to improve its pre-emptive strike capabilities against the North.

Donald Trump has agreed with South Korea's leader, Moon Jae-in, to "maximise pressure" on Pyongyang.