North Korea on Tuesday blew up an inter-Korean liaison office in its border city of Kaesong, making good on a previous threat to leave the "useless" office "completely collapsed."
South Korea's Ministry of Unification confirmed the demolition of the office, saying the explosion occurred at 2:49 pm KST.
The sister of North Korean Supreme Leader Kim Jong Un, Kim Yo Jong, had alluded to the action on Saturday, warning that the South would soon witness the "tragic scene of the useless North-South joint liaison office completely collapsed."
The demolished liaison office first opened in September 2018, in accordance with the Panmunjom Declaration in April of that year, and was located in a city that houses a joint industrial area that has been shut down since 2016 following a round of North Korean nuclear tests.
In the hours after the explosion, South Korea expressed "strong regret" over the destruction of the liaison office, with the Presidential Blue House saying the act "breaches the hope of all people wishing for the development of inter-Korean relations and a lasting peace on the Korean peninsula."
The South Korean government added that it "sternly warns that if [the North] takes steps further aggravating the situation, we will respond strongly."
South Korean Vice Minister of Unification Suh Ho, who co-headed the liaison office, called the demolition a "violation of the Panmunjom Declaration" and a "unilateral breach of the Agreement Concerning the Establishment and Operation of South-North Liaison Offices."
The South Korean military also has adjusted its posture toward the North, with the Ministry of National Defense saying it would respond strongly to any military provocation.
The liaison office's destruction comes amid a low point in inter-Korean relations, with the North severing all communications with the South earlier this month over a diplomatic spat involving propaganda leaflets being scattered across the border.
The leaflets, which contained messages insulting Kim Jong Un and criticizing the North's nuclear ambitions, were distributed by activist groups in the South, drawing a rebuke from the office of President Moon Jae-in last Thursday.
But the North's sharp escalation of the situation didn't come as a surprise to Ahn Chan-il, a North Korean defector and the head of World Institute For North Korea Studies.
"I expected the North would do that. I noticed that would happen once the North lowered its flags at a guard post in the Demilitarized Zone," Ahn told VICE News, explaining that lowering the flags typically indicates a state of emergency or quasi-war.
"It intended to show that Kim Yo Jong's warnings are not empty words and it is a clear sign that it wants to keep the South at a distance."
He added that future provocations would depend on the South's reaction, positioning the liaison office's demolition on the lower end of a sliding scale, with the firing of a submarine-launched ballistic missile at the upper end.
Ahn said he expected the North to intensify the level of provocation around June 25, the 70th anniversary of the start of the Korean War.
Park Sang-hak, a leader of the Fighters for a Free North Korea (FFNK), an activist group run by North Korean defectors that organizes leaflet drops, has previously vowed to go ahead with plans to send another one million leaflets over the border on June 25.
Meanwhile, another North Korea expert, Go Myong-hyun, a research fellow at the Asan Institute for Policy Studies, told VICE News that the North's most recent bellicose wasn't just aimed at the South, but also its allies in the U.S., whom the North has recently castigated for what they characterized as the Trump administration's hypocritical approach to engagement.
"The North is likely to escalate the level of provocations, not only against Seoul, but also against Washington," Go said.
And the move could also have domestic implications in the North.
"We can say that there would be a high possibility that Kim Yo Jong would take power as a second boss, or even as a Supreme Leader," Go continued. "The only weakness of Kim Yo Jong's career was that she did not have experience related to the military. North Korea is connecting her with the military for the future."
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