The powerful sister of North Korean leader Kim Jong Un warned Saturday that Seoul would face a "horrible disaster" if unmanned drones reached Pyongyang again, a day after accusing the South of launching such aircraft at the capital.

North Korea on Friday said the South had sent drones carrying propaganda leaflets into Pyongyang's airspace on Oct. 3, and then again on Wednesday and Thursday this week.

South Korean Defense Minister Kim Yong-hyun initially denied the claim, but the Joint Chiefs of Staff later amended that position, saying in a statement that they "cannot confirm whether the North Korean allegations are true or not."