A North Korean reconnaissance plane was found to have flown over the Yellow Sea on Monday of last week, shortly after Pyongyang fired some 110 artillery shells into waters around the inter-Korean maritime border from its coastal batteries.

A military official said Tuesday that the South Korean military spotted an unmanned reconnaissance plane presumed to belong to the North flying at a low altitude near the Northern Limit Line (NLL) on Monday night last week, or shortly after the North fired artillery into waters around the NLL in the Yellow Sea.

The official said the plane had flown to a spot some 20 kilometers north of South Korea’s Yeonpyeong Island at an altitude of some 50 meters.