Explosions were set off over several hours in front of foreign journalists at what North Korea says was its nuclear test site in the mountains in the country's northeast region, The Associated Press reported.
Sky News correspondent Tom Cheshire witnessed the explosion.
"They counted it down - three, two, one. There was a huge explosion, you could just feel it. Dust came at you, the heat came at you. It was extremely loud. It blew an observation cabin made out of wood to complete smithereens," Cheshire reported.
The blasts were set off on three tunnels into the site and observation towers.
The closing of the testing site had been announced as a step leading up to the summit between President Donald Trump and North Korea's leader Kim Jong Un, the AP reported.
Trump’s administration and the North Korean leader were scheduled to come to the table next month, but recently leaders have been verbally volleying shots at each other.
Recently, Vice President Mike Pence made comments during a Fox News interview that compared North Korea to Libya. Libya stopped its weapons program then shortly after it's leader was overthrown and eventually killed, the AP reported.
North Korea’s vice minister of foreign affairs said that Pence’s comments were “ignorant” and “stupid.”
Choe Son Hui told North Korea’s state-run news agency “Whether the U.S. will meet us at a meeting room or encounter us at nuclear-to-nuclear showdown is entirely dependent upon the decision and behavior of the United States.”
Trump, during a meeting with South Korean President Moon Jae-in this week said that the summit could be delayed or canceled, the AP reported.