North Korea says border artillery units ordered to be ready to shoot amid drone tension

North Korea announced Sunday that it had ordered its artillery units near the South Korean border to be fully prepared for potential strikes following threats of a "horrible disaster" over alleged drone flights over its capital.

Pyongyang accused South Korea of sending unmanned drones into its airspace three times this month, Seoul-based Yonhap News reported.

In a statement released by state media, Kim Yo-jong, the influential sister of leader Kim Jong-un, asserted that North Korea is prepared to take "strong retaliatory action" if drones carrying anti-North materials are flown again, cautioning that an attack could come unexpectedly.

In reaction, South Korea's Defense Ministry said that any attempt by Pyongyang to endanger its citizens would lead to the downfall of the North Korean government.

On Friday, North Korea's Foreign Ministry claimed that South Korean drones with leaflets were spotted over Pyongyang on Oct. 3, as well as on Wednesday and Thursday. North Korea threatened a forceful response if such flights continued.

Initially, South Korea's Defense Minister Kim Yong-hyun denied any military drone incursions across the border, while the Joint Chiefs of Staff later indicated that they could not verify the North's allegations.