“The North has the ability to produce traditional infectious biological warfare agents or toxins and biological weapons,” said a study produced two years ago by the Federation of American Scientists. “If North Korea did choose to employ biological weapons, it probably could use agents like anthrax, plague, or yellow fever against water and food supplies in the South’s rear area.”

Kim Yo Jong may have to wait, however, before the North can actually wage biological warfare. The non-profit Nuclear Threat Initiative in Washington has estimated that North Korea “possesses a range of pathogen samples that could be weaponized, and the technical capabilities to do so, rather than deployed, ready-to-use biological weapons.”

Nonetheless, “Kim Yo Jong’s threats are not hollow statements,” Leif-Eric Easley, professor of international relations at Seoul’s Ewha University, told The Daily Beast. He believed, however, before resorting to weapons of mass destruction, the North Koreans “might fire at leaflet balloons and could even try to shell what they believe to be launch sites in South Korea.”