Prosecutors raided South Korea's Defence Ministry and the presidential National Security Office (NSO) on Thursday as part of an investigation into the death of a Marine in 2023 during a rescue operation, local media reported.

Special Prosecutor Lee Myeong-hyeon's team conducted the raids amid allegations that top military officials and the presidential office intervened in an initial probe into the death of Lance Corporal Chae Su-geun, who was swept away in a swollen stream during a search for torrential rain victims in July 2023, Yonhap News Agency reported.

The team is investigating the alleged interference of former President Yoon Suk-yeol in the investigation into Chae's death.

Military investigators had concluded that Lim Seong-geun, then-commander of the Marine Corps 1st Division, and seven other officers bore responsibility for the incident and sought to transfer them to police on negligent homicide and other charges.

The team reportedly plans to seize NSO meeting minutes related to Yoon's alleged resentment over the results of the military's investigation into the death and materials on the Defence Ministry's responses to media reports on the death.