No South Korean military unmanned aerial vehicle has entered North Korean skies, the South Korean Joint Chiefs of Staff said Friday in response to North Korean Foreign Ministry claims of such infiltration into Pyongyang.

“The South Korean military has not sent any UAVs or flyers. We don’t know yet if a civilian drone flew in,” an official from the South’s JCS told The Korea Herald.

In a statement, the North’s Foreign Ministry claimed that South Korean UAVs had flown over central Pyongyang late Thursday and dropped propaganda leaflets. The ministry said this was the third such infiltration by a South Korean UAV this month.

The ministry said letting the UAVs fly over the North Korean capital was an “unforgivable act” and a “serious attack” that South Korea “must pay a price for.”

The ministry added it has mobilized “all means of attack to destroy the South Korean military” near the inter-Korean border to be “ready for action at any moment.”

In a short message to reporters, the JCS declined to confirm whether the claims by the North's Foreign Ministry are true.

“We cannot verify the claims by North Korea,” the JCS said. “The responsibility for the recent events lies entirely with North Korea, which has been waging despicable acts of provocation such as launches of trash balloons that are an international embarrassment.”

The JCS urged North Korea to “exercise restraint” and emphasized that the South Korean military would “respond decisively and forcefully if the safety of our people is threatened in any way.”