North Korea blew up an office set up to foster better ties with South Korea in a "terrific explosion" yesterday after it threatened to take action if North Korean defectors went ahead with a campaign to send propaganda leaflets into the North.
North Korea's KCNA state news agency said the liaison office in the border town of Kaesong, which had been closed since January due to the coronavirus crisis, was "completely ruined".
Black-and-white surveillance video released by South Korea's ministry of defence showed a large explosion that appeared to bring down the four-storey structure.
The blast also appeared to cause a partial collapse of a neighbouring 15-storey high-rise that had served as a residential facility for South Korean officials who staffed the liaison office.
The office, when it was operating, effectively served as an embassy for the old rivals and its destruction represents a major setback to efforts by South Korean President Moon Jae-in to coax the North into co-operation.
South Korea's national security council convened an emergency meeting yesterday, and said South Korea would sternly respond if North Korea continued to raise tensions.
The destruction of the office "broke the expectations of all people who hope for the development of inter-Korean relations and lasting peace on the peninsula", deputy national security advisor Kim You-geun told a briefing.
"We're making clear that the North is entirely responsible for all the consequences this might cause," he said.
Reclusive North Korea, whose nuclear and missile programmes are the subject of stalled talks with the United States, and the democratic South are technically still at war because their 1950-53 conflict ended in a truce, not a treaty.
Tension has been rising over recent days, with the North threatening to cut ties with the South and retaliate over the propaganda leaflets, which carry messages critical of North Korean leader Kim Jong-un, including on human rights.
The demolition was "unprecedented in inter-Korean relations" and a "nonsensical act that should have not happened", South Korean vice unification minister Suh Ho, who co-headed the liaison office, told reporters.
KCNA said the office was blown up to force "human scum and those, who have sheltered the scum, to pay dearly for their crimes".
North Korea refers to defectors as "human scum".
The first diplomatic mission of its kind, the liaison office was established in 2018 as part of a series of projects aimed at reducing tensions between the two Koreas.