Seoul, January 11 (QNA) - South Korean President Lee Jae Myung on Saturday ordered a prompt investigation into alleged drone incursions into North Korea, warning that such acts would constitute "a grave crime" threatening peace on the Korean Peninsula and national security if confirmed.

North Korea claimed earlier in the day that South Korea had infringed on its sovereignty with drone incursions last September and again earlier this week, but Seoul's defense ministry rejected Pyongyang's accusations, according to (Yonhap) News Agency.

Addressing the possibility that the drones were operated by a private individual or group, Lee said if the allegation proves true, it would amount to "a serious crime that threatens peace on the Korean Peninsula and national security," calling on the military and police to conduct a swift and thorough probe. (QNA)