North Korea "blew up" inter-Korean liaison office, Seoul says

North Korea "destroyed' a joint liaison office building on its side of the border on Tuesday, Seoul’s Unification Ministry said, per AP.

Details: "North Korea blew up the inter-Korean liaison office" in the border town of Kaesong, South Korea’s Unification Ministry said via text message, according to Bloomberg. Smoke could be seen and "an explosion was heard" in town, Yonhap notes.

Driving the news: The South Korean news agency reported there had been "near-daily threats to punish Seoul over anti-Pyongyang propaganda leaflets." Kim Yo-jong, the sister of North Korean leader Kim Jong Un, warned in statements this month via the state-run KCNA news agency that South Korea could "pay a dear price" for its actions.

• She stepped up her rhetoric on Saturday night, saying: "Before long, a tragic scene of the useless North-South joint liaison office completely collapsed would be seen."
• North Korean military officials said earlier Tuesday they were studying an "action plan" to enter the demilitarised zone dividing the two Koreas to "turn the front line into a fortress and further heighten military vigilance against the South," according to KCNA.
• The North Korean regime "abandoned its operations at the facility that once allowed the rivals to communicate around the clock" about a week ago, per Bloomberg.

Of note: Kim Yo-jong has continued to rise in prominence since working to protect her brother's image in the North Korean regime's propaganda department in 2014, becoming the first member of the ruling family to visit South Korea during the 2018 Winter Olympics since the Korean War in 1950, according to the BBC.

• She was mentioned as the North Korean dictator's possible successor when he vanished in April as rumors swirled about his health.

Editor's note: This article and headline have been updated with new details throughout, including to clarify the location of this event.