SEOUL, South Korea (AP) — North Korea said Saturday it found the remains of a South Korean drone during a search in its capital, Pyongyang, claiming the drone proved the South’s military was behind the alleged drone infiltrations over the city’s skies earlier in the month.

North Korea accused South Korea of flying propaganda-filled drones over Pyongyang and threatened “retaliation,” state media reported Friday.

North Korea said on Saturday it had discovered the remains of a crashed South Korean military drone, suggesting it was on a propaganda mission in the latest confrontation between the two involving cross-border flying objects.