A drone suspected of being flown into the Democratic People's Republic of Korea (DPRK) is alleged to have involved two former staffers of the presidential office under the Republic of Korea (ROK)'s ex-President Yoon Suk-yeol, Yonhap News Agency reported on Sunday.

The two men, both in their 30s and former employees at the Yongsan presidential office, are under investigation by a joint military-police team.

One suspect is believed to have built the drone, while the other claimed he flew it to measure radiation and heavy-metal contamination levels near a uranium facility along the Ryesong River in the DPRK. The pair co-founded a drone startup in 2024.

Earlier this month, the DPRK accused ROK of violating its airspace by flying a drone on January 4, according to the Korean Central News Agency.

Police are examining the motive and circumstances of the alleged flight, including the possibility that the two suspects colluded in operating the drone.

(With input from Xinhua)