North Korea has accused South Korea of flying drones over Pyongyang, alleging they dropped anti-North Korean propaganda leaflets, a move it described as crossing a 'red line' and a potential cause for armed conflict. South Korea's military has denied these allegations, advising North Korea to exercise restraint. North Korea has threatened military retaliation if such incidents occur again, calling the alleged drone activity a 'grave political and military provocation.' The tensions have been further exacerbated by North Korea's continued weapons tests and South Korea's military exercises with the United States. South Korean activists have previously used balloons to send leaflets across the border, though no group has claimed responsibility for the current accusations. Despite the ongoing tensions, both Koreas remain technically at war, as their conflict ended with an armistice rather than a peace treaty.