North Korea has carried out what it says is the demolition of its nuclear test site, setting off a series of explosions over several hours in the presence of foreign journalists.
Thursday's explosions at the nuclear test site deep in the mountains of the North's sparsely populated northeast were centred on three tunnels at the underground site and a number of buildings in the surrounding area.
The planned closing was previously announced by leader Kim Jong-un ahead of his planned summit with US President Donald Trump, which is scheduled to take place next month.
The demolition came as the North lobbed another verbal salvo at Washington, calling Vice President Mike Pence a "political dummy" and saying it is just as ready to meet in a nuclear confrontation as at the negotiating table.
The North's decision to close the Punggye-ri nuclear test site has generally been seen as a welcome gesture by Kim to set a positive tone ahead of the summit.
Even so, it is not an irreversible move and would need to be followed by many more significant measures to meet Trump's demands for real denuclearisation.
By bringing in a small group of television journalists and other members of the news media, the North is likely hoping to have dramatic images of the closing - including explosions to collapse tunnel entrances - broadcast around the world.
The North did not invite international nuclear weapons inspectors to the ceremony.
The first blast visiting journalists witnessed happened at around 11am local time. North Korean officials said it collapsed the north tunnel, which was used for five nuclear tests between 2009 and last year.
Two other explosions in the afternoon demolished the west and south tunnels, according to officials.
Thursday's demolition also involved the destruction of observation posts and barracks used by guards and other workers at the facility.
The journalists who were allowed to witness the demolition arrived in the morning and stayed at the site for around nine hours.
Getting to the remote site required an 11-hour overnight train journey from Wonsan, a port city east of the capital, Pyongyang.
The summit plan has hit a number of speed bumps recently as both sides have begun trading barbs and taking tougher positions. Trump met with South Korean President Moon Jae-in on Tuesday at the White House for consultations and suggested the summit could be delayed or even called off entirely.
Even so, both sides still seem to want to hold the meeting.
