Prosecutors say they have obtained concrete evidence that high-ranking officials intervened with an investigation into the 2023 death of a Marine.

Assistant counselor Choung Min-young said Thursday that the team is seeking the pretrial detention of two former prosecutors in recognition of the gravity of the charges against them.

Choung said the two suspects, Kim Seon-gyu and Song Chan-jin, had undermined the purpose of the Corruption Investigation Office for High-ranking Officials(CIO), which is to investigate crimes outside the influence of those in power.

On Wednesday, the team sought detention of the two former prosecutors with close ties to the former president, on charges of power abuse.

Prosecutors believe that Kim disrupted the probe into the death of a Marine, who drowned during a search operation in 2023, by instructing investigators not to interrogate involved individuals ahead of the general elections last April while serving as the CIO's acting chief.

The team suspects that Song obstructed the acquisition and execution of a search warrant for the former president's personal mobile phone and extension number at the presidential office.

Detention hearings are scheduled for Monday.